Effects of distinct drugs on gene transcription in an osteosarcoma cell line

Cuproptosis signature and PLCD3 predicts immune infiltration and drug responses in osteosarcoma

Osteosarcoma (OS) is a cancer that is frequently found in children and adolescents and has made little improvement in terms of prognosis in recent years. A recently discovered type of programmed cell death called cuproptosis is mediated by copper ions and the tricarboxylic acid (TCA) cycle. The expression patterns, roles, and prognostic and predictive capabilities of the cuproptosis regulating genes were investigated in this work. TARGET and GEO provided transcriptional profiling of OS. To find different cuproptosis gene expression patterns, consensus clustering was used. To identify hub genes linked to cuproptosis, differential expression (DE) and weighted gene co-expression network analysis (WGCNA) were used. Cox regression and Random Survival Forest were used to build an evaluation model for prognosis. For various clusters/subgroups, GSVA, mRNAsi, and other immune infiltration experiments were carried out. The drug-responsive study was carried out by the Oncopredict algorithm. Cuproptosis genes displayed two unique patterns of expression, and high expression of FDX1 was associated with a poor outcome in OS patients. The TCA cycle and other tumor-promoting pathways were validated by the functional study, and activation of the cuproptosis genes may also be connected with immunosuppressive state. The robust survival prediction ability of a five-gene prognostic model was verified. This rating method also took stemness and immunosuppressive characteristics into account. Additionally, it can be associated with a higher sensitivity to medications that block PI3K/AKT/mTOR signaling as well as numerous chemoresistances. U2OS cell migration and proliferation may be encouraged by PLCD3. The relevance of PLCD3 in immunotherapy prediction was verified. The prognostic significance, expressing patterns, and functions of cuproptosis in OS were revealed in this work on a preliminary basis. The cuproptosis-related scoring model worked well for predicting prognosis and chemoresistance.

Identification of critical genes associated with human osteosarcoma metastasis based on integrated gene expression profiling

Osteosarcoma is the most common type of malignant bone cancer, which often affects teenagers and young adults. The present study aimed to screen for critical genes and microRNAs (miRNAs/miRs) involved in osteosarcoma. A total of four microarray datasets (accession numbers GSE32981, GSE21257, GSE14827 and GSE14359) were downloaded from the Gene Expression Omnibus database. Following data preprocessing, module analysis was performed to identify the stable modules using the weighted gene co‑expression network analysis (WGCNA) package. The differentially expressed genes (DEGs) between metastatic samples and non‑metastatic samples were screened, followed by gene co‑expression network construction, and Gene Ontology function and Kyoto Encyclopedia of Genes and Genomes pathway analyses. Subsequently, prognosis‑associated genes were screened and a miRNA‑target gene regulatory network was constructed. Finally, the data for critical genes were validated. WGCNA analysis identified six modules; blue and yellow modules were significantly positively associated with osteosarcoma metastasis. A total of 1,613 DEGs were screened between primary tissue samples and metastatic samples. Following comparison of the genes in the two (blue and yellow) modules, a total of 166 DEGs were identified (metastatic samples vs. non‑metastatic samples). Functional enrichment analysis demonstrated that these DEGs were mainly involved in 'defense response', 'p53 signaling pathway' and 'lysosome'. By utilizing the clinical information in GSE21257, 10 critical genes associated with osteosarcoma prognosis were obtained, including CTP synthase 2 (CTPS2), tumor protein p53 inducible protein 3 (TP53I3) and solute carrier family 1 member 1 (SLC1A1). In addition, hsa‑miR‑422a and hsa‑miR‑194 were highlighted in the miRNA‑target gene network. Finally, matrix metallopeptidase 3 (MMP3) and vascular endothelial growth factor B (VEGFB) were predicted as critical genes in osteosarcoma metastasis. CTPS2, TP53I3 and SLC1A1 may serve major roles in osteosarcoma development, and hsa‑miR‑422a, hsa‑miR‑194, MMP3 and VEGFB may be associated with osteosarcoma metastasis.

Ras-related protein Rap2c promotes the migration and invasion of human osteosarcoma cells

Ras-related protein (Rap)2a and Rap2b are members of the GTP-binding protein family, and serve an important function in tumor progression. However, the associations between Rap2c and cancer cell functions have not yet been reported. Osteosarcoma is a type of bone cancer; its high degree of invasion is considered to be a major treatment challenge. The present study first investigated the biological role of Rap2c in human osteosarcoma cells and investigated the underlying mechanism of Rap2c on osteosarcoma cell migration and invasion. The results of the present study demonstrated that Rap2c overexpression promoted the migratory and invasive ability of cancer cells, and increased the activity of matrix metalloproteinase-2 (MMP2). Correspondingly, the knockdown of Rap2c inhibited tumor cell migration and invasion, whereas alterations to Rap2c had no effect on osteosarcoma cell proliferation or rate of apoptosis. Furthermore, Rap2c overexpression may decrease the protein level of tissue inhibitor of metalloproteinases 2 and increase the phosphorylation level of protein kinase B (Akt). Collectively, these results indicated that Rap2c has a key function in tumor migration and invasion, and the Akt signaling pathway may be involved in Rap2c-induced MMP2 expression.