A non-disruptive and efficient knock-in approach allows fate tracing of resident osteoblast progenitors during repair of vertebral lesions in medaka.

During bone development and repair, osteoblasts are recruited to bone deposition sites. To identify the origin of recruited osteoblasts, cell lineage tracing using Cre/loxP recombination is commonly used. However, a confounding factor is the use of transgenic Cre drivers that do not accurately recapitulate endogenous gene expression or the use of knock-in Cre drivers that alter endogenous protein activity or levels. Here, we describe a CRISPR/Cas9 homology-directed repair knock-in approach that allows efficient generation of Cre drivers controlled by the endogenous gene promoter. In addition, a self-cleaving peptide preserves the reading frame of the endogenous protein. Using this approach, we generated col10a1p2a-CreERT2 knock-in medaka and show that tamoxifen-inducible CreERT2 efficiently recombined loxP sites in col10a1 cells. Similar knock-in efficiencies were obtained when two unrelated loci (osr1 and col2a1a) were targeted. Using live imaging, we traced the fate of col10a1 osteoblast progenitors during bone lesion repair in the medaka vertebral column. We show that col10a1 cells at neural arches represent a mobilizable cellular source for bone repair. Together, our study describes a previously unreported strategy for precise cell lineage tracing via efficient and non-disruptive knock-in of Cre.

Upregulation of collagen type X alpha 1 promotes the progress of triple-negative breast cancer via Wnt/ß-catenin signaling.

Triple-negative breast cancer (TNBC) is a malignant tumor with high degree of malignancy and lack of effective target treatment. The research aims to explore the role and mechanism of X collagen alpha-1 chain protein (COL10A1 gene) in TNBC. UALCAN and Kaplan-Meier were used to detect the expression of COL10A1 and its role in the prognosis of breast cancer patients. The cells with stably expressing high levels of COL10A1 were obtained by recombinant lentivirus infection. The expression of COL10A1 in cells was temporarily downregulated by siRNA interference fragments. Real-time quantitative polymerase chain reaction and western blot analysis were utilized to detect the changes of COL10A1 mRNA and protein expression. The biological functions of the cells were evaluated by colony formation, cell counting kit-8, cell invasion and wound healing experiments. In addition, the effect of COL10A1 on angiogenesis was investigated by tube formation assay. Xenograft tumor model was used to confirm the effect of COL10A1 on tumorigenicity in vivo and multiplex fluorescent immunohistochemistry to detect multiple proteins simultaneously. The possible molecular mechanism of the function of COL10A1 was speculated through the detection of proteins in functionally related pathways. COL10A1 is highly expressed and is significantly associated with worse overall survival (OS) and recurrence-free survival (RFS) in TNBC. Overexpression of COL10A1 increased the clone formation rate and cell migration capacity of TNBC cells. In the COL10A1 overexpression group, the clone formation rates of MD-MB-231 and BT-549 cells (21.5 ± 0.62, 27.83 ± 3.72)% were significantly higher than those in the control group(15.23 ± 2.79, 19.4 ± 1.47)%, and the relative migration ratio (47.40 ± 3.09, 41.26 ± 4.33)% were higher than those in the control group (34.48 ± 2.03, 21.80 ± 1.03)%. When the expression of COL10A1 was downregulated, the ability of clone formation and wound-healing migration capacity in TNBC cells was weakened. Upregulated COL10A1 in TNBC cells generated more junctions and longer total segments between vascular endothelial cells, and promoted angiogenesis of the cells, and thus enhanced the tumorigenesis. In TNBC, it was found that COL10A1 might affect epithelial-mesenchymal transition (EMT) of the cells through Wnt/ß-catenin signaling pathway by the detection of the related pathway proteins. COL10A1 is highly expressed in TNBC, and its high expression leads to poor OS and RFS. COL10A1 may enhance TNBC cell proliferation, migration and tumor-related angiogenesis, and promote tumorigenesis in vivo via Wnt/ß-catenin signaling.

Krüppel-like factor 4 modulates the miR-101/COL10A1 axis to inhibit renal fibrosis after AKI by regulating epithelial-mesenchymal transition.

Acute kidney injury (AKI) can progress to renal fibrosis and chronic kidney disease (CKD), which reduces quality of life and increases the economic burden on patients. However, the molecular mechanisms underlying renal fibrosis following AKI remain unclear. This study tested the hypothesis that the Krüppel-like factor 4 (KLF4)/miR-101/Collagen alpha-1X (COL10A1) axis could inhibit epithelial-mesenchymal transition (EMT) and renal fibrosis after AKI in a mouse model of ischemia-reperfusion (I/R)-induced renal fibrosis and HK-2 cells by gene silencing, overexpression, immunofluorescence, immunohistochemistry, real-time quantitative PCR, Western blotting, dual-luciferase reporter assay, fluorescence in situ hybridization (FISH) and ELISA. Compared with the Sham group, I/R induced renal tubular and glomerular injury and fibrosis, and increased the levels of BUN, serum Scr and neutrophil gelatinase-associated lipocalin (NGAL), Col10a1 and Vimentin expression, but decreased E-cadherin expression in the kidney tissues of mice at 42 days post-I/R. Similarly, hypoxia promoted fibroblastic morphological changes in HK-2 cells and enhanced NGAL, COL10A1, Vimentin, and α-SMA expression, but reduced E-cadherin expression in HK-2 cells. These pathological changes were significantly mitigated in COL10A1-silenced renal tissues and HK-2 cells. KLF4 induces miR-101 transcription. More importantly, hypoxia upregulated Vimentin and COL10A1 expression, but decreased miR-101, KLF4, and E-cadherin expression in HK-2 cells. These hypoxic effects were significantly mitigated or abrogated by KLF4 over-expression in the HK-2 cells. Our data indicate that KLF4 up-regulates miR-101 expression, leading to the downregulation of COL10A1 expression, inhibition of EMT and renal fibrosis during the pathogenic process of I/R-related renal fibrosis.

COL10A1 promotes tumorigenesis by modulating CD276 in pancreatic adenocarcinoma.

BACKGROUND: Pancreatic adenocarcinoma (PAAD) is a lethal malignant tumour. Further study is needed to determine the molecular mechanism and identify novel biomarkers of PAAD. METHODS: Gene expression data from the GSE62165 microarray were analysed with the online software Morpheus to identify differentially expressed genes (DEGs). The STRING database was used to generate a protein‒protein interaction (PPI) network for these DEGs. Hub genes were identified with Cytoscape. COL10A1 expression in PAAD was analysed via the GEPIA database. COL10A1 expression in pancreatic cancer cell lines was measured by using qRT‒PCR. The LinkedOmics database was utilized to perform survival analysis of pancreatic adenocarcinoma patients grouped based on COL10A1 expression level. CCK-8, wound healing, and Transwell assays were used to study the role of COL10A1 in pancreatic cancer cell viability, migration, and invasion. Differentially expressed genes that were related to COL10A1 in PAAD were analysed via the LinkedOmics portal. After COL10A1 was knocked down, CD276 expression was assessed by western blotting. RESULTS: COL10A1 was identified as one of the hub genes in PAAD by bioinformatics analysis of the GSE62165 microarray with Morpheus, the STRING database and Cytoscape. GEPIA revealed elevated expression of COL10A1 in PAAD samples vs. normal samples. COL10A1 expression was also increased in pancreatic cancer cells vs. control cells. Survival analysis of PAAD patients via LinkedOmics revealed that high expression of COL10A1 was associated with a poorer prognosis. Knockdown of COL10A1 inhibited the proliferation, migration, and invasion of cells in functional assays. Furthermore, mechanistic studies indicated that CD276 was a target of COL10A1 and that knockdown of COL10A1 decreased CD276 expression. Overexpression of CD276 in cells reversed COL10A1 knockdown-induced repression of proliferation and migration. CONCLUSIONS: Our research suggests that COL10A1 promotes pancreatic adenocarcinoma tumorigenesis by regulating CD276. This study provides new insight into biomarkers and possible targets for pancreatic cancer treatment.

COL10A1 is a novel factor in the development of choroidal neovascularization.

With the dramatic rise in the aging population, researching age-related macular degeneration (AMD), especially the severe form neovascular AMD (nAMD), has become more important than ever. In this study, we found that collagen type X was increased in retina-choroid tissue of mice with laser-induced choroidal neovascularization (CNV) based on immunohistofluorescence. RNA sequencing and bioinformatic analyses were performed to compare the retina-choroid tissue complex of the CNV mouse model to normal controls. Collagen type X alpha 1 chain (Col10a1) was among the most significantly upregulated genes, and the results were validated with an animal model at the mRNA and protein levels by quantitative real-time polymerase chain reaction (qPCR) and western blotting, respectively. COL10A1 was also upregulated in human retinal microvascular endothelial cells (HRMECs), human umbilical vein endothelial cells (HUVECs), RPE19 cells and RF/6A cells under hypoxic conditions. Next, in vitro and in vivo experiments were performed to study the effect of COL10A1 on neovascularization. siRNA knockdown of COL10A1 suppressed the proliferation and tube formation ability of HRMECs under hypoxic conditions. Snail family transcriptional repressor 1 (SNAIL1) and angiopoietin-2 (ANGPT2) were downregulated in COL10A1 knockdown HRMECs under hypoxic conditions and thus were potential downstream genes. Significant decreases in CNV leakage and CNV lesion area, as assessed by fundus fluorescein angiography (FFA) and immunofluorescence of choroidal flat mounts, respectively, were observed in a mouse model intravitreally injected with anti-collagen X monoclonal antibody (mAb) compared to the controls. In conclusion, COL10A1 promotes CNV formation and may represent a new candidate target for the treatment and diagnosis of nAMD and other neovascular diseases.

High COL10A1 expression potentially contributes to poor outcomes in gastric cancer with the help of LEF1 and Wnt2.

BACKGROUND: COL10A1 is a secreted, short-chain collagen found in several types of cancer. Studies have shown that COL10A1 aberrant expression is considered an oncogenic factor. However, its underlying mechanisms and regulation of gastric cancer remain undefined. METHODS: The data on the expression of COL10A1, clinicopathological characteristics, and outcome of patients with GC were obtained from The Cancer Genome Atlas. The ALGGEN-PROMO database defined the related transcription factors. Quantitative real-time reverse transcription-polymerase chain reaction and western blotting analysis were used to identify the differential expression levels of COL10A1 and related transcription factors. RESULTS: We found that high COL10A1 expression is an independent risk factor for gastric cancer. Upregulation of LEF1 and Wnt2 was also observed in gastric cancer, suggesting a potential correlation between LEF1/COL10A1 regulation in the Wnt2 signaling pathway. CONCLUSION: High COL10A1 expression may contribute to poor outcomes via upregulation of LEF1 and Wnt2 in gastric cancer.

Identification of two novel COL10A1 heterozygous mutations in two Chinese pedigrees with Schmid-type metaphyseal chondrodysplasia.

BACKGROUND: Schmid-type metaphyseal chondrodysplasia (MCDS) is an autosomal dominant disorder caused by COL10A1 mutations, which is characterized by short stature, waddling gait, coxa vara and bowing of the long bones. However, descriptions of the expressivity of MCDS are rare. METHODS: Two probands and available family members affected with MCDS were subjected to clinical and radiological examination. Genomic DNA of all affected individuals was subjected to whole-exome sequencing, and candidate mutations were verified by Sanger sequencing in all available family members and in 250 healthy donors. A spatial model of the type X collagen (α1) C-terminal noncollagenous (NC1) domain was further constructed. RESULTS: We found that the phenotype of affected family members exhibited incomplete dominance. Mutation analysis indicated that there were two novel heterozygous missense mutations, [c.1765 T > A (p.Phe589Ile)] and [c.1846A > G (p.Lys616Glu)] in the COL10A1 gene in family 1 and 2, respectively. The two novel substitution sites were highly conserved and the mutations were predicted to be deleterious by in silico analysis. Furthermore, protein modeling revealed that the two substitutions were located in the NC1 domain of collagen X (α1), which potentially impacted the trimerization of collagen X (α1) and combination with molecules in the pericellular matrix. CONCLUSION: Two novel mutations were identified in the present study, which will facilitate diagnosis of MCDS and further expand the spectrum of the COL10A1 mutations associated with MCDS patients. In addition, our research revealed the phenomenon of incomplete dominance in MCDS.

Autosomal recessive chondrodysplasia with severe short stature caused by a biallelic COL10A1 variant.

BACKGROUND: Heterozygous mutations in COL10A1 underlie metaphyseal chondrodysplasia, Schmid type (MCDS), an autosomal dominant skeletal dysplasia. OBJECTIVE: To identify the causative variant in a large consanguineous Pakistani family with severe skeletal dysplasia and marked lower limb deformity. METHODS: Whole exome sequencing was completed followed by Sanger sequencing to verify segregation of the identified variants. In silico variant pathogenicity predictions and amino acid conservation analyses were performed. RESULTS: A homozygous c.133 C>T (p.Pro45Ser) variant was identified in COL10A1 in all six severely affected individuals (adult heights 119-130 cm, mean ~-6.33 SD). The individuals heterozygous for the variant had mild phenotype of short stature (adult heights 140-162 cm, mean ~-2.15 SD) but no apparent skeletal deformities. The variant was predicted to be pathogenic by in silico prediction tools and was absent from public databases and hundred control chromosomes. Pro45 is conserved in orthologues and is located in the non-collagenous 2 domain of COL10A1, variants of which have never been associated with skeletal dysplasia. CONCLUSIONS: This first report of individuals with a homozygous variant in COL10A1 defines a new type of autosomal recessive skeletal dysplasia. The observations in COL10A1 variant carriers suggest a phenotypic overlap between the mildest forms of MCDS and idiopathic short stature.

Association study of candidate genes for susceptibility to Kashin-Beck disease in a Tibetan population.

BACKGROUND: Many osteoarthritis (OA) susceptibility genes have been identified in recent years. Given the overlap in the phenotype of joint inflammation between OA and Kashin-Beck disease (KBD), the aim of this study is to explore whether the reported OA susceptibility genes and two genes that may link to OA pathophysiology are associated with KBD in the Tibetan population. METHOD: Fifteen single-nucleotide polymorphisms (SNPs) in 12 candidate genes previously reported as OA susceptibility loci were selected for investigation. Genotyping was performed using the SNaPshot method for these SNPs in a Tibetan population composed of 849 KBD patients and 565 normal controls. Meanwhile, the coding regions of two genes, COL10A1 and HABP2, which may involve in the pathological mechanism of OA/KBD, were sequenced by Sanger sequencing to identify susceptibility coding variants for KBD in the Tibetan population. RESULTS: The two arthritis-susceptible candidate SNPs, rs7775 (p.Arg324Gly) in the FRZB gene and rs7033979 in the ASPN gene, showed associations with KBD (OR = 1.568, P = 4 × 10-3 and OR = 0.744, P = 8 × 10-3, respectively). The coding variants rs142463796 (p.Asp128Asn) and rs2228547 (p.Gly545Arg) in the COL10A1 gene (OR = 9.832 and P = 6 × 10-3 and OR = 1.242, P = 0.043, respectively) and rs548354451 (p.Asp272Glu) in the HABP2 gene (OR = 2.813, P = 0.010) were associated with KBD patients. CONCLUSION: These finding suggested that rs7775 in the FRZB gene may increase susceptibility to KBD, while rs7033979 in the ASPN gene may play a protective role in susceptibility to KBD in Tibetans. Moreover, genetic variants in chondrogenesis-related genes COL10A1 and HABP2 may play a role in the risk of developing KBD in the Tibetan population.

Indian hedgehog signaling regulates transcription and expression of collagen type X via Runx2/Smads interactions.

Indian hedgehog (Ihh) is essential for chondrocyte differentiation and endochondral ossification and acts with parathyroid hormone-related peptide in a negative feedback loop to regulate early chondrocyte differentiation and entry to hypertrophic differentiation. Independent of this function, we and others recently reported independent Ihh functions to promote chondrocyte hypertrophy and matrix mineralization in vivo and in vitro. However, the molecular mechanisms for these actions and their functional significance are still unknown. We recently discovered that Ihh overexpression in chondrocytes stimulated the expression of late chondrocyte differentiation markers and induced matrix mineralization. Focusing on collagen type X (Col10α1) expression and transcription, we observed that hedgehog downstream transcription factors GLI-Krüppel family members (Gli) 1/2 increased COL10A1 promoter activity and identified a novel Gli1/2 response element in the 250-bp basic promoter. In addition, we found that Ihh induced Runx2 expression in chondrocytes without up-regulating other modulators of chondrocyte maturation such as Mef2c, Foxa2, and Foxa3. Runx2 promoted Col10α1 expression in cooperation with Ihh. Further analyses using promoter assays, immunofluorescence, and binding assays showed the interaction of Gli1/2 in a complex with Runx2/Smads induces chondrocyte differentiation. Finally, we could demonstrate that Ihh promotes in vitro matrix mineralization using similar molecular mechanisms. Our data provide an in vitro mechanism for Ihh signaling to positively regulate Col10α1 transcription. Thus, Ihh signaling could be an important player for not only early chondrocyte differentiation but maturation and calcification of chondrocytes.

Collagen type X expression and chondrocyte hypertrophic differentiation during OA and OS development.

Chondrocyte hypertrophy and the expression of its specific marker, the collagen type X gene (COL10A1), constitute key terminal differentiation stages during endochondral ossification in long bone development. Mutations in the COL10A1 gene are known to cause schmid type metaphyseal chondrodysplasia (SMCD) and spondyloepiphyseal dyschondrodysplasia (SMD). Moreover, abnormal COL10A1 expression and aberrant chondrocyte hypertrophy are strongly correlated with skeletal diseases, notably osteoarthritis (OA) and osteosarcoma (OS). Throughout the progression of OA, articular chondrocytes undergo substantial changes in gene expression and phenotype, including a transition to a hypertrophic-like state characterized by the expression of collagen type X, matrix metalloproteinase-13, and alkaline phosphatase. This state is similar to the process of endochondral ossification during cartilage development. OS, the most common pediatric bone cancer, exhibits characteristics of abnormal bone formation alongside the presence of tumor tissue containing cartilaginous components. This observation suggests a potential role for chondrogenesis in the development of OS. A deeper understanding of the shifts in collagen X expression and chondrocyte hypertrophy phenotypes in OA or OS may offer novel insights into their pathogenesis, thereby paving the way for potential therapeutic interventions. This review systematically summarizes the findings from multiple OA models (e.g., transgenic, surgically-induced, mechanically-loaded, and chemically-induced OA models), with a particular focus on their chondrogenic and/or hypertrophic phenotypes and possible signaling pathways. The OS phenotypes and pathogenesis in relation to chondrogenesis, collagen X expression, chondrocyte (hypertrophic) differentiation, and their regulatory mechanisms were also discussed. Together, this review provides novel insights into OA and OS therapeutics, possibly by intervening the process of abnormal endochondral-like pathway with altered collagen type X expression.

Oncogenic mechanisms of COL10A1 in cancer and clinical challenges (Review).

Collagen type X α1 chain (COL10A1), a gene encoding the α­1 chain of type X collagen, serves a key role in conferring tensile strength and structural integrity to tissues. Upregulation of COL10A1 expression has been observed in different malignancies, including lung, gastric and pancreatic cancer, and is associated with poor prognosis. The present review provides an updated synthesis of the evolving biological understanding of COL10A1, with a particular focus on its mechanisms of action and regulatory functions within the context of tumorigenesis. For example, it has been established that increased COL10A1 expression promotes cancer progression by activating multiple signaling pathways, including the TGF­ß1/Smad, MEK/ERK and focal adhesion kinase signaling pathways, thereby inducing proliferation, invasion and migration. Additionally, COL10A1 has been demonstrated to induce epithelial­mesenchymal transition and reshapes the extracellular matrix within tumor tissues. Furthermore, on the basis of methyltransferase­like 3­mediated N6­methyladenosine methylation, COL10A1 intricately regulates the epitranscriptomic machinery, thereby augmenting its oncogenic role. However, although COL10A1 serves a pivotal role in gene transcription and the orchestration of tumor growth, the question of whether COL10A1 would serve as a viable therapeutic target remains a subject of scientific hypothesis requiring rigorous examination. Variables such as distinct tumor microenvironments and treatment associations necessitate further experimental validation. Therefore, a comprehensive assessment and understanding of the functional and mechanistic roles of COL10A1 in cancer may pave the way for the development of innovative cancer treatment strategies.

Ddx5 participates in regulation of Col10a1 expression and chondrocyte hypertrophic differentiation in vitro.

BACKGROUND AND AIMS: The type X collagen gene (Col10a1), is a specific molecular marker of hypertrophic chondrocytes during endochondral ossification. Col10a1 expression is known to be influenced by many regulators. In this study, we aim to investigate how DEAD-box helicase 5 (DDX5), a potential binding factor for Col10a1 enhancer, may play a role in Col10a1 expression and chondrocyte hypertrophic differentiation in vitro. METHODS: The potential binding factors of the 150-bp Col10a1 cis-enhancer were identified with the hTFtarget database. The expression of DDX5 and COL10A1 was detected by quantitative real-time PCR (qRT-PCR) and Western blot in chondrogenic ATDC5 and MCT cell models with or without Ddx5 knockdown or overexpression. Dual-luciferase reporter assay and chromatin immunoprecipitation (ChIP) were performed to determine the interaction between DDX5 and the Col10a1 enhancer. The effect and mechanism of DDX5 on chondrocyte differentiation and maturation was evaluated by alcian blue, alkaline phosphatase (ALP), and alizarin red staining in ATDC5 cell lines with stable knockdown of Ddx5. RESULTS: DDX5 was identified as a potential binding factor for the Col10a1 enhancer. The expression of DDX5 in hypertrophic chondrocytes was higher than that in proliferative chondrocytes. Knockdown of Ddx5 decreased, while overexpression of Ddx5 slightly increased COL10A1 expression. DDX5 promotes the enhancer activity of Col10a1 as demonstrated by dual-luciferase reporter assay, and the ChIP experiment suggests a direct interaction between DDX5 and the Col10a1 enhancer. Compared to the control (NC) group, we observed weaker alcian blue and ALP staining intensity in the Ddx5 knockdown group of ATDC5 cells cultured both for 7 and 14 days. Whereas weaker alizarin red staining intensity was only found in the Ddx5 knockdown group of cells cultured for 7 days. Meanwhile, knockdown of Ddx5 significantly reduced the level of runt-related transcription factor 2 (RUNX2) in related ATDC5 cells examined. CONCLUSIONS: Our results suggest that DDX5 acts as a positive regulator for Col10a1 expression and may cooperate with RUNX2 together to control Col10a1 expression and promote the proliferation and maturation of chondrocytes.

COL10A1 as a Prognostic Biomarker in Association with Immune Infiltration in Prostate Cancer.

BACKGROUND: The collagen type X alpha 1 (COL10A1) has recently been found to play an important role in the development and progression of cancer. However, the link between COL10A1 and the tumor immune microenvironment remains understood scantily. METHODS: In the current study, the pan-cancer data of The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were used to investigate the expression mode, the clinical prognostic and diagnostic value of COL10A1 in different tumors. We used TCGA data to assess the correlations between COL10A1 and clinical symptoms of prostate cancer. The R packages "edgR" and "clusterProfiler" were used for differential expression gene and enrichment analysis of COL10A1. Immunohistochemistry was further employed to corroborate the expression of COL10A1 gene in prostate cancer. After that, we used TIMER to evaluate the pertinence of COL10A1 expression to immune infiltration level in prostate cancer. RESULTS: On the whole, COL10A1 was expressed at significantly higher levels in a variety of tumor tissues than in the corresponding normal tissues. Besides, significant correlations with tumor prognosis and relative exactitude in predicting tumors show that COL10A1 may be a probable prognostic and diagnostic biomarker of prostate cancer. In addition, the evidence indicates a significant correlation between COL10A1 and clinical symptoms of prostate cancer. Furthermore, the main molecular functions of COL10A1 included humoral immune response, complement activation, immunoglobulin, regulation of complement activation, and regulation of humoral immune response. Finally, we found that COL10A1 expression is positively correlated with enhanced macrophage and M2 macrophage infiltration in prostate cancer. CONCLUSION: The study indicates that COL10A1 might participate in M2 macrophage polarization in prostate cancer. COL10A1 might be an innovative biomarker to evaluate tumor microenvironment immune cell infiltration and prognosis in prostate cancer.

The Osteoblast Transcriptome in Developing Zebrafish Reveals Key Roles for Extracellular Matrix Proteins Col10a1a and Fbln1 in Skeletal Development and Homeostasis.

Zebrafish are now widely used to study skeletal development and bone-related diseases. To that end, understanding osteoblast differentiation and function, the expression of essential transcription factors, signaling molecules, and extracellular matrix proteins is crucial. We isolated Sp7-expressing osteoblasts from 4-day-old larvae using a fluorescent reporter. We identified two distinct subpopulations and characterized their specific transcriptome as well as their structural, regulatory, and signaling profile. Based on their differential expression in these subpopulations, we generated mutants for the extracellular matrix protein genes col10a1a and fbln1 to study their functions. The col10a1a-/- mutant larvae display reduced chondrocranium size and decreased bone mineralization, while in adults a reduced vertebral thickness and tissue mineral density, and fusion of the caudal fin vertebrae were observed. In contrast, fbln1-/- mutants showed an increased mineralization of cranial elements and a reduced ceratohyal angle in larvae, while in adults a significantly increased vertebral centra thickness, length, volume, surface area, and tissue mineral density was observed. In addition, absence of the opercle specifically on the right side was observed. Transcriptomic analysis reveals up-regulation of genes involved in collagen biosynthesis and down-regulation of Fgf8 signaling in fbln1-/- mutants. Taken together, our results highlight the importance of bone extracellular matrix protein genes col10a1a and fbln1 in skeletal development and homeostasis.

Interleukin 6 mediates selected effects of Notch in chondrocytes.

OBJECTIVE: Notch receptors determine cell fate by regulating transcription, an event mediated by the Notch intracellular domain (NICD), which is generated by proteolysis brought about by Notch-ligand interactions. Since Notch activation or exposure to interleukin (Il)6 have similar effects in chondrocytes, we explored whether interleukin 6 (Il6) contributes to the mechanisms of Notch action in these cells. METHOD: NICD was overexpressed in primary chondrocytes from Rosa(Notch) mice, where the Rosa26 promoter precedes a loxP-flanked STOP cassette followed by the NICD coding sequence. Cells were infected with adenoviral vectors expressing Cre to induce NICD or green fluorescent protein (GFP) as control. Gene expression was determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Il6 protein concentration in the culture media was determined by enzyme-linked immunosorbent assay (ELISA). To test the mechanisms of Notch action on Il6 expression, cells were transfected with a fragment of the Il6 promoter or control vector pGL3, or transcriptionally arrested with 5,6-dichloro-1-ß-d-ribofuranosylbenzimidazole. Il6 was inhibited with a neutralizing antibody, whereas a normal immunoglobulin G (IgG) was used as control. RESULTS: NICD induced Il6 mRNA and protein, and transactivated the Il6 promoter without affecting Il6 mRNA stability. Il6 neutralization had no impact on gene expression under basal conditions, and did not modify the effects of NICD on sex determining region-Y-related high mobility group-box gene (Sox)9, collagen type II α1 (Col2a1) and collagen type X α1 (Col10a1) expression. Conversely, Il6 neutralization opposed aggrecan (Acan) suppression and prevented matrix metalloprotease (Mmp)13 induction by NICD. CONCLUSION: Il6 mediates suppression of Acan and induction of Mmp13 expression by Notch in chondrocytes.

COL10A1 is a potential immunotherapy biomarker associated with immune infiltration and deficient mismatch repair in colon cancer.

Aim: Our study aimed to identify the role of COL10A1 in colon cancer, including interaction with immune infiltrates and somatic mutations. Methods: COL10A1 expression and prognostic value were assessed. Correlations between COL10A1 and various immune parameters were conducted by bioinformatic analysis. Results: Our study demonstrated that COL10A1 is overexpressed in colon cancer and correlates with poor patient survival. The expression level of COL10A1 is significantly associated with mismatch repair deficiency and immune infiltration. High expression of COL10A1 may confer greater sensitivity to anti-PD-1 treatment in colon cancer patients. Conclusion: COL10A1 is a potential diagnostic biomarker associated with deficient mismatch repair and immune infiltration in colon cancer.

Colorectal cancer (CRC) is a deadly disease and we do not have a cure. Immunotherapy is a new method that can help CRC patients to live longer, but it only works for some people. To find out who will get good results with immunotherapy, we looked at a protein named COL10A1. We found more COL10A1 in colon cancer tissues than in healthy tissues. CRC patients with a lot of COL10A1 are more likely to die than those patients with low levels of this protein. COL10A1 can interact with some immune cells and by looking at how much COL10A1 is in different CRC patients, we may be able to choose the right patients to treat with immunotherapy.

Experimental validation and pan-cancer analysis identified COL10A1 as a novel oncogene and potential therapeutic target in prostate cancer.

BACKGROUND: Type X collagen (COL10) is a homologous trimeric non-fibrillar collagen found in the extracellular matrix of human tissues, and it exhibits a distinctive white appearance. Type X collagen α1 chain (COL10A1) is a specific cleaved fragment of type X collagen. However, the expression, prognostic significance, clinicopathological attributes and immune-related associations of COL10A1 in prostate cancer as well as in pan-cancer contexts remain poorly understood. METHODS: Using bioinformatic analysis of data from the most recent databases (TCGA, GTEx and GEO databases), we have extensively elucidated the role played by COL10A1 in terms of its expression patterns, prognostic implications, and immune efficacy across a pan-cancer spectrum. Subsequently, the biological functions of COL10A1 in prostate cancer were elucidated by experimental validation. RESULTS: Our findings have confirmed that COL10A1 was highly expressed in most cancers and was associated with poorer prognosis in cancer patients. Immune correlation analysis of COL10A1 in various cancers showed its significant correlation with Tumor mutational burden (TMB), microsatellite instability (MSI) and immune cell infiltration. In addition, knockdown of COL10A1 in prostate cancer resulted in a substantial reduction in the proliferation, migration, and invasive potential of prostate cancer cells. CONCLUSION: Our pan-cancer analysis of COL10A1 gene provided novel insights into its pivotal role in cancer initiation, progression, and therapeutic implications, underscoring its potential significance in prognosis and immunotherapeutic interventions for cancer, particularly prostate cancer.

Natural history and genetic spectrum of the Turkish metaphyseal dysplasia cohort, including rare types caused by biallelic COL10A1, COL2A1, and LBR variants.

BACKGROUND: Metaphyseal chondrodysplasias are a heterogeneous group of diseases characterized by short and bowed long bones and metaphyseal abnormality. The aim of this study is to investigate the genetic etiology and prognostic findings in patients with metaphyseal dysplasia. METHODS: Twenty-four Turkish patients were included in this study and 13 of them were followed for 2-21 years. COL10A1, RMRP sequencing and whole exome sequencing were performed. RESULTS: Results: Seven heterozygous pathogenic variants in COL10A1 were detected in 17 patients with Schmid type metaphyseal chondrodysplasia(MCDS). The phenotype was more severe in patients with heterozygous missense variants (one in signal peptide domain at the N-terminus of the protein, the other, class-1 group mutation at NC1 domain) compared to the patients with truncating variants. Short stature and coxa vara deformity appeared after 3 and 5 years of age, respectively, while large femoral head resolved after the age of 13 years in MCDS group. Interestingly, one patient with severe phenotype also had a biallelic missense variant in NC1 domain of COL10A1. Three patients with biallelic mutations in RMRP had prenatal onset short stature with short limb, and typical findings of cartilage hair hypoplasia (CHH). While immunodeficiency or recurrent infections were not observed, resistant congenital anemia was detected in one. Biallelic mutation in LBR was described in a patient with prenatal onset short stature, short and curved limb and metaphyseal abnormalities. Unlike previously reported patients, this patient had ectodermal findings, similar to CHH. A biallelic COL2A1 mutation was also found in the patient with lower limb deformities and metaphyseal involvement without vertebral and epiphyseal changes. CONCLUSION: Long-term clinical characteristics are presented in a metaphyseal dysplasia cohort, including rare types caused by biallelic COL10A1, COL2A1, and LBR variants. We also point out that the domains where mutations on COL10A1 take place are important in the genotype-phenotype relationship.

Prognostic value of COL10A1 and its correlation with tumor-infiltrating immune cells in urothelial bladder cancer: A comprehensive study based on bioinformatics and clinical analysis validation.

Introduction: Bladder cancer (BLCA) is one of the most lethal diseases. COL10A1 is secreted small-chain collagen in the extracellular matrix associated with various tumors, including gastric, colon, breast, and lung cancer. However, the role of COL10A1 in BLCA remains unclear. This is the first research focusing on the prognostic value of COL10A1 in BLCA. In this research, we aimed to uncover the association between COL10A1 and the prognosis, as well as other clinicopathological parameters in BLCA. Methods: We obtained gene expression profiles of BLCA and normal tissues from the TCGA, GEO, and ArrayExpress databases. Immunohistochemistry staining was performed to investigate the protein expression and prognostic value of COL10A1 in BLCA patients. GO and KEGG enrichment along with GSEA analyses were performed to reveal the biological functions and potential regulatory mechanisms of COL10A1 based on the gene co-expression network. We used the "maftools" R package to display the mutation profiles between the high and low COL10A1 groups. GIPIA2, TIMER, and CIBERSORT algorithms were utilized to explore the effect of COL10A1 on the tumor immune microenvironment. Results: We found that COL10A1 was upregulated in the BLCA samples, and increased COL10A1 expression was related to poor overall survival. Functional annotation of 200 co-expressed genes positively correlated with COL10A1 expression, including GO, KEGG, and GSEA enrichment analyses, indicated that COL10A1 was basically involved in the extracellular matrix, protein modification, molecular binding, ECM-receptor interaction, protein digestion and absorption, focal adhesion, and PI3K-Akt signaling pathway. The most commonly mutated genes of BLCA were different between high and low COL10A1 groups. Tumor immune infiltrating analyses showed that COL10A1 might have an essential role in recruiting infiltrating immune cells and regulating immunity in BLCA, thus affecting prognosis. Finally, external datasets and biospecimens were used, and the results further validated the aberrant expression of COL10A1 in BLCA samples. Conclusions: In conclusion, our study demonstrates that COL10A1 is an underlying prognostic and predictive biomarker in BLCA.