Osteosarcoma Patients Research Articles

Integrated immunogenomic analyses of single-cell and bulk profiling construct a T cell-related signature for predicting prognosis and treatment response in osteosarcoma

PurposesT cells play a crucial role as regulators of anti-tumor activity within the tumor microenvironment (TME) and are closely associated with the progression of osteosarcoma (OS). Nevertheless, the specific role of T cell-related genes (TCRGs) in the pathogenesis of OS remains unclear.MethodsFirst, we processed single-cell RNA sequencing (scRNA-seq) data of OS from the public databases and performed cell annotation. We identified highly variable genes in each cell type using the "FindAllMarkers" function, explored the distribution of different clusters, and investigated inter-cellular communication patterns via the "CellChat" framework. Then, we used multivariate Cox analysis to construct a TCRG and developed a nomogram to predict survival probabilities for OS patients. Finally, we validated the aforementioned results using various cell lines and investigated the immune cell infiltration, expression of immune checkpoints, chemotherapy sensitivity, and the efficacy of targeted therapies across different risk groups.ResultsFrom the scRNA-seq data, we identified 3,000 highly variable genes, presented the top 10 genes, and validated the expression of core genes across different cell lines.Moreover, our analysis delved into interactions between T cells and other cell types. Our analyses constructed a predictive T cell-related signature (TCRS) that incorporated these prognostic TCRGs, showing a clear prognostic separation between the high-risk and low-risk OS patient groups in multiple cohorts. Survival analysis indicated better outcomes for patients classified in the high-risk group. The low-risk group exhibited elevated levels of CD4 memory resting T cells, contrasting with the higher levels of macrophage M0 observed in the high-risk group via the CIBERSORT algorithm. Furthermore, we observed that the low-risk group exhibitedAQ1 significant up-regulation of immune checkpoint genes (ICGs) and lower Tumour Immune Dysfunction and Exclusion (TIDE) scores, suggesting that they may be suitable for immunotherapy. Conversely, the high-risk group appeared more responsive to chemotherapy and targeted therapies, according to our drug sensitivity analysis.ConclusionIn conclusion, our study identified TCRGs, constructed and validated a TCRS for OS, and assessed immune response and drug sensitivity in different risk groups of OS patients. These findings provide novel insights into personalized treatment strategies for OS, potentially guiding more effective therapeutic interventions.

Curcumin and Methotrexate: A Promising Combination for Osteosarcoma Treatment via Hedgehog Pathway Inhibition

Osteosarcoma (OS) is the most severe bone tumor in children. A chemotherapy regimen includes a combination of high-dose Methotrexate (MTX), doxorubicin, and cisplatin. These drugs cause acute and chronic side effects, such as infections, thrombocytopenia, neutropenia, DNA damage, and inflammation. Therefore, to identify new therapeutic strategies, effective and with a safety profile, is necessary. The Hedgehog (Hh) signaling pathway involved in tumorigenesis is active in OS. Hh components Patched receptor 1 (PTCH1), Smoothened (SMO), and glioma-associated oncogene homolog transcription factors (GLI1 and GLI2) are overexpressed in OS cell lines and patient samples. Curcumin (CUR)—with antioxidant and anti-cancer properties—downregulates Hh components in cancer, inhibiting progression. This study investigates CUR effects on the MG-63 OS cell line, alone and combined with MTX, to propose a novel therapeutic approach. Our study suggests CUR as a novel therapeutic agent in OS, particularly when combined with MTX. Targeting the Hh signaling pathway, CUR and MTX showed significant pro-apoptotic effects, increasing the BAX/Bcl-2 ratio and total apoptotic cell percentage. They reduced the expression of Hh pathway components (PTCH1, SMO, GLI1, and GLI2), inhibiting OS cell proliferation, survival, and invasion. CUR and MTX combined determined a β-Catenin decrease and a trend toward reducing NF-kB and matrix metalloproteinases (MMP-2 and MMP-9). Our findings suggest CUR as a support to OS treatment, improving outcomes and reducing the adverse effects of current therapies.

Large Scale Comparative Analysis of Canine and Human Osteosarcomas Uncovers Conserved Clinically Relevant Tumor Microenvironment Subtypes.

Osteosarcoma is an aggressive bone cancer lacking robust biomarkers for personalized treatment. Despite its scarcity in humans, it is relatively common in adult pet dogs. This study aimed to analyze clinically annotated bulk tumor transcriptomic datasets of canine and human osteosarcoma patients to identify potentially conserved patterns of disease progression. Bulk transcriptomic data from 245 pet dogs with treatment-naïve appendicular osteosarcoma were analyzed using deconvolution to characterize the tumor microenvironment (TME). The TME of both primary and metastatic tumors derived from the same dog was compared, and its impact on canine survival was assessed. A machine learning model was developed to classify the TME based on its inferred composition using canine tumor data. This model was applied to 8 independent human osteosarcoma datasets to assess its generalizability and prognostic value. This study found three distinct TME subtypes of canine osteosarcoma based on cell type composition of bulk tumor samples: Immune Enriched (IE), Immune Enriched Dense Extra-Cellular Matrix-like (IE-ECM), and Immune Desert (ID). These three TME-based subtypes of canine osteosarcomas were conserved in humans and could predict progression-free survival outcomes of human patients, independent of conventional prognostic factors such as percent tumor necrosis post standard of care chemotherapy treatment and disease stage at diagnosis. These findings demonstrate the potential of leveraging data from naturally occurring cancers in canines to model the complexity of the human osteosarcoma TME, offering a promising avenue for the discovery of novel biomarkers and developing more effective precision oncology treatments.

Electrolyte prognosis scoring system can predict overall survival in patients with osteosarcoma.

Osteosarcoma stands as the most prevalent bone tumor, characterized by a heightened tendency for local recurrence and distant metastasis, resulting in a bleak prognosis. Presently, there exists a shortage of novel markers to effectively determine the prognosis of osteosarcoma patients. Recent research indicates that hematological markers partially mirror an individual's microenvironment, offering potential insights into predicting patient prognosis. However, prior studies predominantly focused on the prognostic significance of singular hematological indices, failing to comprehensively represent the tumor microenvironment of patients. In our investigation, we meticulously gathered data on 22 hematological and electrolyte markers, utilizing LASSO Cox regression analysis to devise an Electrolyte Prognostic Scoring System (EPSS). The EPSS encompasses various indicators, including immunity, inflammation, coagulation, and electrolyte levels. Our findings indicate that the EPSS stands as an independent prognostic factor for overall survival among osteosarcoma patients. It serves as a valuable addition to clinical characteristics, adept at discerning high-risk patients from those deemed clinically low-risk. Furthermore, EPSS-based nomograms demonstrate commendable predictive capabilities.

Immune-related glycosylation genes based classification predicts prognosis and therapy options of osteosarcoma

Osteosarcoma is the most common primary bone malignancy, with a very poor prognosis. Aberrant glycosylation is close involvement in osteosarcoma. Accordingly, this study aimed at investigating the role of glycosylation genes in the prognosis and therapy options of osteosarcoma. The microenvironment of osteosarcoma was assessed using estimate algorithm. A total of 20 immune-related glycosylation genes (IRGGs) was identified using Pearson correlation analysis. Accordingly, osteosarcoma patients were divided into C1 and C2 type using consensus clustering. Multiple algorithms (Xcell, MCP-counter, ssGSEA, epic, quantiseq), cancer immune cycle analysis, and GSVA were applied to estimate the immune, molecule and metabolism characteristics of osteosarcoma, indicating that C1 type was featured with high immune infiltration, high glycosylation, enriched MEK signaling, and good prognosis, while C2 type was characterized by more metastasis, enriched immunotherapy-positive gene signatures, high tumor mutation burden, and poor prognosis. Results from TIDE algorithm and immunotherapy datasets suggested the C2 type’s preference of immune checkpoint inhibitors (ICIs), while data of GDSC, CMap analysis and cell experiments indicated that C1 type was sensitivity to MEK inhibitor PD0325901. In addition, univariate Cox and Lasso analysis was combined to establish an IRGGs’ risk score containing 6 genes (B3GNT8, FUT7, GAL3ST4, GALNT14, HS3ST2, and MFNG). The data of DCA and ROC indicated its well prediction of prognosis in osteosarcoma. Finally, cellular location analysis showed that the 6 genes not only distributed in tumor cells but also in immune cells. In summary, the classification and risk score based on IRGGs effectively predicted the prognosis and therapy options of osteosarcoma. Further studies on IRGGs may contribute to the understanding of cancer immunity in osteosarcoma.

IGFBP5 in osteosarcoma tumorigenesis: Gene expression profile among metastatic and non-metastatic patients

Osteosarcoma (OS) is the most frequent primary malignant bone tumor among children and adolescents, with a peak of incidence in the second decade of life. The presence of metastasis at diagnosis in OS patients significantly decreases the chances of survival and new therapy approaches are needed. The IGFBP5 gene is related to osteoblasts metabolism and some studies have pointed out a role of its low expressions in OS development and metastasis. In this study, we aimed to establish an IGFBP5 gene expression profile among metastatic and non-metastatic OS patients throughout the treatment and development of the disease. Fresh-frozen tumor samples were obtained from 40 patients admitted to treatment at the Pediatric Oncology Institute (IOP/GRAACC/UNIFESP) and divided by clinical status: metastatic or non-metastatic disease. For each patient, samples before and after chemotherapy treatment were obtained, as well as metastasis and lung tissue surrounding metastasis samples from the metastatic patients. A quantitative real-time PCR was used to investigate IGFBP5 expression. Our analyses demonstrate that non-metastatic patients presented lower IGFBP5 expression in their pre-chemotherapy samples compared with metastatic patients, suggesting that low expressions of this gene could help triggering the OS tumorigenesis but that its action alone is not sufficient to activate the metastatic process. Heterogeneity in IGFBP5 expressions within groups was also seen. We observed that IGFBP5 and two MAPK genes, a downstream pathway in the IGFBP5 axis, are differentially expressed in OS samples of non-metastatic patients. Further investigation about these genes’ modulations might lead to a better understanding of metastasis development in OS.

Exploring circulating MiRNA signature for osteosarcoma detection: Bioinformatics-based analyzing and validation

Early detection followed by efficient treatment still remain a considerable challenge for osteosarcoma (OS), indicating the importance of emerging innovative diagnostic methods. Circulating miRNAs offer a promising and non-invasive approach to assess the OS molecular landscapes. This study utilized RNAseq data from OS plasma miRNA expression profiles (PRJEB30542) and PCR Array data (GSE65071) from GEO and ENA databases. In total, 43 miRNAs demonstrated significant differential expression in OS samples of training dataset. A diagnostic model, including hsa-miR-30a-5p, hsa-miR-556–3p, hsa-miR-200a-3p, and hsa-miR-582–5p was identified through multivariate logistic regression analysis and demonstrated significant efficacy in differentiating OS patients from healthy controls in the validation group (AUC: 0.917, sensitivity: 1, specificity: 0.85). The result of target gene prediction and functional enrichment analyses revealed significant associations with terms such as epithelial morphogenesis, P53 and Wnt signaling pathways, and neoplasm metastasis. Further bioinformatics-based evaluations showed that the down-regulation of these miRNAs significantly correlates with poor prognosis and lower survival rate in OS patients and propose their tumor suppressor function in pathogenesis of OS. Furthermore, the study developed a miRNA-mRNA subnetwork that connects these miRNAs to the P53 and Wnt signaling pathways, which are critical pathways with oncogenic effects on OS progression. This comprehensive approach not only presents a promising diagnostic model but also proposes potential molecular markers for OS early diagnosis, making prognosis, and targeted therapy. The identified miRNA-mRNA functional axis holds promise as a valuable resource for further research in understanding OS pathogenesis and establishing therapeutic modalities.

Case Report: Pathological fracture in a Li-Fraumeni osteosarcoma patient: "Capasquelet'' femoral reconstruction and tumor vascular analysis with endomucin immunofluorescence multiplexing

We describe the case report of an Osteosarcoma patient, with a Li-Fraumeni Syndrome, presenting with a pathological femoral fracture. The patient was treated with a multidisciplinary approach associating neoadjuvant and adjuvant chemotherapy with excisional surgery. The femoral reconstruction consisted of a ``Capasquelet'' reconstruction combining an induced membrane and a vascularized fibula allograft allowing a good functional result with an early weight-bearing. We managed to complete our histological analysis in this patient, in order to evaluate the tumor vascularization. Indeed, using the syngeneic osteosarcoma MOS-J mouse model, we highlighted previously that CD31+/\ensuremath{\alpha}-SMA+ vessels may be indicators of vasculature normalization and therefore may be used as specific markers of a good therapeutic response. Thus, we search for its interest in this specific case as preliminary work. The aim was to assess the feasibility and technical validity of the vascularization analysis of a human osteosarcoma tumor specimen. Therefore, we propose an immunohistochemistry methodology with multiplexed immunofluorescence to assess the vascularization as a promising marker in human osteosarcoma tissue.

Make it STING: nanotechnological approaches for activating cGAS/STING as an immunomodulatory node in osteosarcoma.

Osteosarcoma is a highly aggressive bone cancer primarily affecting children, adolescents, and young adults. The current gold standard for treatment of osteosarcoma patients consists of two to three rounds of chemotherapy, followed by extensive surgical intervention from total limb reconstruction to amputation, followed by additional rounds of chemotherapy. Although chemotherapy has advanced the treatment of osteosarcoma significantly, the overall 5-year survival rate in resistant forms of osteosarcoma is still below 20%. The interaction between cancer and the immune system has long been recognized as a critical aspect of tumour growth. Tumour cells within the tumour microenvironment (TME) suppress antitumour immunity, and immunosuppressive cells and cytokines provide the extrinsic factors of tumour drug resistance. Emerging research demonstrates an immunostimulatory role for the cGAS/STING pathway in osteosarcoma, typically considered an immune-cold or immunosuppressed cancer type. cGAS/STING signalling appears to drive an innate immune response against tumours and potentiates the efficacy of other common therapies including chemo and radiotherapy. Nanotechnological delivery systems for improved therapy delivery for osteosarcoma have also been under investigation in recent years. This review provides an overview of cGAS/STING signalling, its divergent roles in the context of cancer, and collates current research which activates cGAS/STING as an adjuvant immunomodulatory target for the treatment of osteosarcoma. It will also discuss current nanotechnological delivery approaches that have been developed to stimulate cGAS/STING. Finally, it will highlight the future directions that we believe will be central to the development of this transformative field.

SNPs Give LACTB Oncogene-Like Functions and Prompt Tumor Progression via Dual-Regulating p53.

LACTB is identified as a tumor suppressor in several tumors. However, preliminary study reveals that LACTB is overexpressed in osteosarcoma and indicates poor prognosis. Two missense mutations (rs34317102 and rs2729835) exist simultaneously in 92.31% of osteosarcoma patients and cause M5L and R469K double mutations in LACTB, suggesting the biologic function of LACTB protein may be altered in osteosarcoma. Moreover, LACTBM5L+R469K overexpression can promote malignant progression in different tumors, which suggests that the M5L and R469K mutations confer oncogene-like functions to LACTB. Mechanistically, LACTBM5L+R469K not only reduces the wild type p53 via enhancing PSMB7 catalytic activity, but also protects p53R156P protein from lysosomal degradation, which suggesting LACTBM5L+R469K is a dual-regulator for wt-p53 and mutant p53, and derive oncogene-like functions. More importantly, clavulanate potassium, a bacterial β-lactamase inhibitor, can inhibit osteosarcoma proliferation and sensitize osteosarcoma to cisplatin by binding and blocking LACTBM5L+R469K. These findings revealed that the M5L and R469K double mutations can diminish the tumor suppressive ability of wild type LACTB and provide oncogene-like functions to LACTB. Inhibiting LACTBM5L+R469K can suppress the progression of osteosarcoma harbouring wild-type or mutant p53. Clavulanate potassiumis a promising drug by targeting LACTBM5L+R469K-p53 pathway for the treatment of osteosarcoma patients.

Exploring Mitochondrial Autophagy Dysregulation in Osteosarcoma: Its Implications for Prognosis and Targeted Therapy

Objective: This study aimed to investigate the differential expression of mitophagyrelated genes in osteosarcoma patients with distinct prognostic outcomes and explore potential molecular regulatory mechanisms. Methods: We analyzed microarray data from metastatic and nonmetastatic osteosarcoma patients using the UCSC dataset. Differential gene screening and intersection of mitophagy-related genes were performed using NetworkAnalyst. Random forest and LASSO regression were employed to screen selected genes and establish a risk prediction model. Functional enrichment analysis, protein- protein interaction (PPI) networks, immunoassays, and in vitro experiments were conducted to validate the findings. Results: Seven differentially expressed genes were identified, and a robust risk prediction model was developed (AUC=0.886). PPI and functional enrichment analyses provided insights into relevant molecules and regulatory pathways. The immunoassay results revealed differences in the immune environment between the metastatic and nonmetastatic groups. Immunohistochemistry demonstrated significant downregulation of EPHA3 expression in the metastatic group, and in vitro experiments indicated that inhibiting EPHA3 increased the proliferative activity and migration ability of osteosarcoma cells. Conclusion: Our study suggests that the downregulation of EPHA3 may contribute to mitochondrial autophagy dysfunction, thereby increasing the risk of osteosarcoma metastasis.

COL12A1 Promotes Osteosarcoma Progression via the FAK/PI3K/AKT/mTOR Pathway.

Osteosarcoma (OS) is a common malignancy among adolescents and children, characterized by a high propensity for metastasis and resistance to chemotherapy. This study aimed to investigate the role of COL12A1, a gene often overexpressed in various cancers and associated with poor prognosis, in the progression of OS and explore the underlying mechanisms. The expression pattern and potential function of COL12A1 in OS were evaluated using bioinformatics analyses, clinical sample examination, and OS cell lines. Various assays, including transwell, CCK-8, flow cytometry, and wound healing, were performed to assess the impact of COL12A1 on OS cell growth, cell cycle progression, apoptosis, invasion, and migration. Western blot analysis was conducted to investigate markers associated with the FAK/PI3K/AKT/mTOR pathway. COL12A1 expression was significantly elevated in OS tissues and cells. Upregulation of COL12A1 promoted cell growth, accelerated cell cycle progression, and enhanced migration and invasion while inhibiting apoptosis. Conversely, the knockdown of COL12A1 had the opposite effect. Additionally, COL12A1 overexpression increased the phosphorylation of components in the FAK/PI3K/AKT/mTOR pathway. The FAK inhibitor Y15 mitigated the effects of COL12A1 overexpression on cell apoptosis, invasion, proliferation, and the FAK/PI3K/AKT/mTOR pathway in OS. Our findings indicated that COL12A1 enhanced OS development by activating the FAK/PI3K/AKT/mTOR pathway, suggesting that COL12A1 could serve as a valuable biomarker for the prediction and identification of OS patients.

Inhibition of osteosarcoma metastasis in vivo by targeted downregulation of MMP1 and MMP9

Osteosarcoma (OS) mortality stems from lung metastases. Matrix metalloproteinases (MMPs) facilitate metastatic dissemination by degrading extracellular matrix components. Herein we studied the impact of targeted MMP downregulation on OS metastasis. Differential gene expression analysis of human OS cell lines revealed high MMP9 expression in the majority of OS cell lines. Furthermore, 143B, a metastatic OS cell line, exhibited increased MMP1 and MMP9 mRNA levels. Gene set enrichment analysis on metastatic and non-metastatic OS patient specimens indicated epithelial-mesenchymal transition as the most enriched gene set, with MMP9 displaying strong association to genes in this network. Using the same dataset, Kaplan-Meier analysis revealed a correlation between MMP1 expression and dismal patient survival. Hence, we undertook targeted suppression of MMP1 and MMP9 gene expression in OS cell lines. The ability of OS cells to migrate and form colonies was markedly reduced upon MMP1 and MMP9 downregulation, whereas their cell proliferation capacity remained intact. MMP9 downregulation decreased tumor growth and lung metastases area in an orthotopic mouse OS model. Consistently, human OS lung metastasis specimens displayed marked MMP9 protein expression. Our findings highlight the role of MMP1 and MMP9 in OS metastasis, warranting further exploration of simultaneous inhibition of MMPs for future OS therapeutics.

Multi-omics and Single Cell Sequencing Analyses Reveal Associations of Mitophagy-Related Genes Predicting Clinical Prognosis and Immune Infiltration Characteristics in Osteosarcoma.

Despite recent advances in clinical treatments, identifying high-risk osteosarcoma (OS) patients remains an unresolved clinical challenge. Mitophagy, a specialized form of cellular autophagy, selectively reduces the number of mitochondria or repairs their abnormal functions in response to external stress, thereby ensuring mitochondrial quality and maintaining mitochondrial function. Mitophagy plays a crucial role in cancer development, including processes such as mitochondrial repair, homeostasis maintenance, and tumor metabolism. However, its impact on OS has not yet been reported. In this study, we collected 58 mitophagy-related genes (MPRGs) from the TARGET and GEO databases and bioinformatically screened for those associated with OS prognosis. By LASSO-multivariable Cox regression algorithm, we subsequently developed a novel scoring system, the MPRG score, and validated its significance in predicting OS prognosis. Immune landscape analysis showed patients in the low MPRG group had a higher immune infiltration level than those in the high MPRG group. Drug sensitivity differences highlighted the potential need for alternative therapeutic strategies based on MPRG scoring system. The distribution characteristics of the MPRG signature in different cell subtypes of OS were explored by single-cell sequencing analyses. In vitro experiments further confirmed the abnormal expression of screened targets in OS. Our findings highlight the role of mitophagy in OS and its potential as a therapeutic target.

A useful mTORC1 signaling-related RiskScore model for the personalized treatment of osteosarcoma patients by using the bulk RNA-seq analysis

AimsThis research developed a prognostic model for OS patients based on the Mechanistic Target of Rapamycin Complex 1 (mTORC1) signature.BackgroundThe mTORC1 signaling pathway has a critical role in the maintenance of cellular homeostasis and tumorigenesis and development through the regulation of cell growth, metabolism and autophagy. However, the mechanism of action of this signaling pathway in Osteosarcoma (OS) remains unclear.ObjectiveThe datasets including the TARGET-OS and GSE39058, and 200 mTORC1 genes were collected.MethodsThe mTORC1 signaling-related genes were obtained based on the Molecular Signatures Database (MSigDB) database, and the single sample gene set enrichment analysis (ssGSEA) algorithm was utilized in order to calculate the mTORC1 score. Then, the WGCNA were performed for the mTORC1-correlated gene module, the un/multivariate and lasso Cox regression analysis were conducted for the RiskScore model. The immune infiltration analysis was performed by using the ssGSEA method, ESTIMATE tool and MCP-Count algorithm. KM survival and Receiver Operating Characteristic (ROC) Curve analysis were performed by using the survival and timeROC package.ResultsThe mTORC1 score and WGCNA with β = 5 screened the mTORC1 positively correlated skyblue2 module that included 67 genes, which are also associated with the metabolism and hypoxia pathways. Further narrowing of candidate genes and calculating the regression coefficient, we developed a useful and reliable RiskScore model, which can classify the patients in the training and validation set into high and low-risk groups based on the median value of RiskScore as an independent and robust prognostic factor. High-risk patients had a significantly poor prognosis, lower immune infiltration level of multiple immune cells and prone to cancer metastasis. Finally, we a nomogram model incorporating the metastasis features and RiskScore showed excellent prediction accuracy and clinical practicability.ConclusionWe developed a useful and reliable risk prognosis model based on the mTORC1 signaling signature.

MTA2 knockdown suppresses human osteosarcoma metastasis by inhibiting uPA expression.

The relationship between metastasis-associated protein 2 (MTA2) overexpression and tumor growth and metastasis has been extensively studied in a variety of tumor cells but not in human osteosarcoma cells. This study aims to elucidate the clinical significance, underlying molecular mechanisms, and biological functions of MTA2 in human osteosarcoma in vitro and in vivo. Our results show that MTA2 was elevated in osteosarcoma cell lines and osteosarcoma tissues and was associated with tumor stage and overall survival of osteosarcoma patients. Knockdown of MTA2 inhibited osteosarcoma cell migration and invasion by reducing the expression of urokinase-type plasminogen activator (uPA). Bioinformatic analysis demonstrated that high levels of uPA in human osteosarcoma tissues correlated positively with MTA2 expression. Furthermore, treatment with recombinant human uPA (Rh-uPA) caused significant restoration of OS cell migration and invasion in MTA2 knockdown osteosarcoma cells. We found that ERK1/2 depletion increased the expression of uPA, facilitating osteosarcoma cell migration and invasion. Finally, MTA2 depletion significantly reduced tumor metastasis and the formation of lung nodules in vivo. Overall, our study suggests that MTA2 knockdown suppresses osteosarcoma cell metastasis by decreasing uPA expression via ERK signaling. This finding provides new insight into potential treatment strategies against osteosarcoma metastasis by targeting MTA2.

Unraveling the role of bisphenol A in osteosarcoma biology: insights into prognosis and immune microenvironment modulation

BackgroundBisphenol A (BPA) is a common environmental pollutant, and its specific mechanisms in cancer development and its impact on the tumor immune microenvironment are not yet fully understood.MethodsTranscriptome data from osteosarcoma (OS) patients were downloaded from the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database. BPA-related genes were identified through the Comparative Toxicogenomics Database (CTD), yielding 177 genes. Differentially expressed genes were analyzed using the GSE162454 dataset from the Tumor Immune Single Cell Hub 2 (TISCH2). We constructed the prognostic model using univariate Cox regression and LASSO analysis. The model was validated using the GSE16091 dataset. GO, KEGG, and GSEA analyses were performed to investigate the mechanisms of BPA-related genes.ResultsA total of 15 BPA-related genes were identified as differentially expressed in OS. Univariate Cox regression and LASSO analysis identified four key prognostic genes (FOLR1, MYC, ESRRA, VEGFA). The prognostic model exhibited strong predictive performance with area under the curve (AUC) values of 0.89, 0.6, and 0.79 for predicting 1-, 2-, and 3-year survival, respectively. External validation using the GSE16091 dataset confirmed the model's high accuracy with AUC values exceeding 0.88. Our results indicated that the prognosis of the high-risk population is generally poorer, which may be associated with alterations in the tumor immune microenvironment. In the high-risk group, immune cells showed predominantly low expression levels, while immune checkpoint genes were significantly overexpressed, along with markedly elevated tumor purity. These findings revealed a correlation between upregulation of BPA-related genes and formation of an immunosuppressive microenvironment, leading to unfavorable patient outcomes.ConclusionOur study highlighted the significant association of BPA with OS biology, particularly in its potential role in modulating the tumor immune microenvironment. We offered a fresh insight into the influence of BPA on cancer development, thus providing valuable insights for future clinical interventions and treatment strategies.

Comprehensive analysis of splicing factor SRs-related gene characteristics: predicting osteosarcoma prognosis and immune regulation status.

To investigate the impact of SRs-related genes on the overall survival and prognosis of osteosarcoma patients through bulk and single-cell RNA-seq transcriptome analysis. In this study, we constructed a prognosis model based on serine/arginine-rich splicing factors (SRs) and predicted the survival of osteosarcoma patients. By analyzing single-cell RNA sequencing data and applying AUCell enrichment analysis, we revealed oncogenic pathways of SRs in osteosarcoma immune cells. Additionally, we described the regulatory role of SRSF7 in pan-cancer. Lasso regression analysis identified 6 key SRs-related genes, and a prognosis prediction model was established. The upregulation of these pathways revealed that SRs promote tumor cell proliferation and survival by regulating related signaling pathways and help tumor cells evade host immune surveillance. Additionally, by grouping single-cell data using AUCell, we found significant differences in T cell expression between high and low-risk groups. The analysis results indicated that the regulatory activity of SRs is closely related to T cell function, particularly in regulating immune responses and promoting immune evasion. Furthermore, SRSF7 regulates cell proliferation and apoptosis. SRs-related genes play a critical regulatory role in osteosarcoma. T cells are key in regulating immune responses and promoting immune evasion through SRs genes. SRSF7 is a significant gene influencing the occurrence and development of osteosarcoma.

Prognostic signature and immunotherapeutic relevance of Focal adhesion signaling pathway-related genes in osteosarcoma

BackgroundAs the most common primary malignant bone tumor in children and adolescents, osteosarcoma currently lacks an effective clinical cure. Focal adhesion plays a crucial role in tumor invasion, migration, and drug resistance by mediating communication between the extracellular matrix and tumor cells. This study investigated the prognostic features and immunotherapeutic relevance of focal adhesion pathway-related genes in osteosarcoma to aid in the development of new therapeutic options. MethodsWe obtained mutational, transcriptomic, gene expression, and clinical data of osteosarcoma patients from the Gene Expression Omnibus (GEO) and Therapeutically Applicable Research to Generate Effective (TARGET) databases. Differentially expressed genes were screened, followed by the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses. Kaplan-Meier survival analysis was performed for genes related to the focal adhesion pathway, and multivariate Cox regression analysis was employed to construct a prognostic signature model. Genes such as SIGLEC15, TIGIT, CD274, HAVCR2, PDCD1, CTLA4, and LAG3 were extracted from the TARGET and CCLE databases for osteosarcoma patients and osteosarcoma cell lines, respectively，to observe the expression of immune checkpoint-related genes. Finally, qRT-PCR was used to verify the expression of these immune checkpoint-related genes in osteosarcoma cell lines. ResultsIn our study, 376 samples were analyzed, including 369 osteosarcoma samples and 7 normal tissue samples. We identified 50 up-regulated and 28 down-regulated differentially expressed genes. Among these, 10 Candidate genes relative to focal Adhesion were selected， and CAV1, ZYX, and ITGA5 were found to have a significant prognostic role based on survival analysis of osteosarcoma samples from the TARGET database. A predictive signature model related to the focal adhesion signaling pathway was constructed using these genes, and the AUCs of the 1-year, 3-year, and 5-year ROC curves were 0. 647, 0. 712, and 0. 717, respectively. The overall survival (OS) rate of osteosarcoma patients with high-risk scores was poorer than those with low-risk scores. Then, samples were divided into two subgroups based on the expression of the three genes, revealing significant differences in the expression of certain immune checkpoint-related genes between the subgroups. Additionally, above three genes and immune checkpoint-related genes in osteosarcoma cell lines were extracted from the CCLE database, showing high expression levels in eight osteosarcoma cell lines. We observed that CD274 and PDCD1LG2 were highly expressed in some osteosarcoma cell lines. Finally, the expression of CAV1, ZYX, ITGA5, CD80, CD274, and PDCD1LG2 in osteosarcoma cell lines was verified by qRT-PCR. ConclusionsOur study validated the prognostic role of three focal adhesion pathway-related genes (ZYX, CAV1, and ITGA5) in patients with osteosarcoma and constructed a prognostic signature model associated with the focal adhesion signaling pathway. We identified significant differences in the expression of multiple immune checkpoint-related genes among subgroups defined by the three genes. Additionally, CD274 and PDCD1LG2 showed higher expression in osteosarcoma cell lines characterized by these genes. These findings may aid in the selection of effective immunotherapy for specific osteosarcoma patients.

The efficacy of gemcitabine and docetaxel chemotherapy for the treatment of relapsed and refractory osteosarcoma: A systematic review and pre-clinical study.

Osteosarcoma is the most common primary malignancy of the bone. There is a lack of effective treatments for patients who experience relapsed osteosarcoma. One treatment for relapsed patients is gemcitabine and docetaxel combination chemotherapy (GEMDOX). This systematic review aimed to establish the efficacy of this chemotherapy regimen, as well as identify the common severe toxicities that are associated with it. Resistant osteosarcoma cell lines developed from MG-63 and HOS-143B were used to represent relapsed osteosarcoma patients in a pre-clinical study. We identified 11 retrospective and Phase II studies that were suitable for inclusion in our review. 10.65% of patients had a response to gemcitabine and docetaxel combination therapy and the disease control rate was 35% (n = 197). 36%, 35.3% and 18.04% of patients experienced grade 3 or 4 neutropenia, thrombocytopenia and anaemia respectively (n = 133). Male patients (X2 = 9.14, p < 0.05) and those below the age of 18 (X 2 = 10.94, p < 0.05) responded better to GEMDOX treatment than females and patients older than 18 years. The resistant osteosarcoma cell lines remained sensitive to either single-agent gemcitabine, docetaxel, and the combination of both. Cisplatin-resistant models (MG-63/CISR8 & HOS-143B/CISR8) were the most responsive to GEMDOX treatment compared to doxorubicin, methotrexate, and triple-combination resistant models. GEMDOX treatment has potential efficacy in relapsed osteosarcoma patients especially those with cisplatin resistance. To directly compare the efficacy of GEMDOX therapy against other therapies randomised phase III clinical trials with adequate patient follow up must be performed to improve treatment options for osteosarcoma.