IGFBP6 is a novel nasopharyngeal carcinoma prognostic biomarker

Ferroptosis-Related Genes Are Associated with Radioresistance and Immune Suppression in Head and Neck Cancer

Background: Ferroptosis is associated with tumor development; however, its contribution to radioresistant head and neck cancer (HNC) remains unclear. In this study, we used bioinformatics analysis and in vitro testing to explore ferroptosis-related genes associated with HNCs radiosensitivity. Materials and Methods: GSE9714, GSE90761, and The Cancer Genome Atlas (TCGA) datasets were searched to identify ferroptosis-related differentially expressed genes between radioresistant and radiosensitive HNCs or radiation-treated and nonradiation-treated HNCs. A protein-protein interaction analysis on identified hub genes was then performed. Receiver operating characteristic curves and Kaplan-Meier survival analysis were used to assess the diagnostic and prognostic potential of the hub genes. Cell counting kit-8, transwell assay, and flow cytometry were applied to examine the role of hub gene collagen type IV, alpha1 chain (COL4A1) on the proliferation, migration, invasion, and apoptosis of TU686 cells. Results: Hub genes MMP10, MMP1, COL4A1, IFI27, and INHBA showed diagnostic potential for HNC and were negatively correlated with overall survival and disease-free survival in the TCGA dataset. Also, IL-1B, IFI27, INHBA, and COL4A1 mRNA levels were significantly increased in TCGA patients with advanced clinical stages or receiving radiotherapy, whereas COL4A1, MMP10, and INHBA expressions were negatively correlated with immune infiltration. Furthermore, the knockdown of COL4A1 inhibited cell proliferation, migration, and invasion while promoting apoptosis in TU686 cells. Conclusion: Ferroptosis-related hub genes, such as COL4A1, are potential diagnostic and prognostic indicators as well as therapeutic targets for HNC.

Expression characteristics and their functional role of IGFBP gene family in pan-cancer

BACKGROUND

Insulin-like growth factor binding proteins (IGFBPs) are critical regulators of the biological activities of insulin-like growth factors. The IGFBP family plays diverse roles in different types of cancer, which we still lack comprehensive and pleiotropic understandings so far.

METHODS

Multi-source and multi-dimensional data, extracted from The Cancer Genome Atlas (TCGA), Oncomine, Cancer Cell Line Encyclopedia (CCLE), and the Human Protein Atlas (HPA) was used for bioinformatics analysis by R language. Immunohistochemistry and qRT-PCR were performed to validate the results of the database analysis results. Bibliometrics and literature review were used for summarizing the research progress of IGFBPs in the field of tumor.

RESULTS

The members of IGFBP gene family are differentially expressed in various cancer types. IGFBPs expression can affect prognosis of different cancers. The expression of IGFBPs expression is associated with multiple signal transduction pathways. The expression of IGFBPs is significantly correlated with tumor mutational burden, microsatellite instability, tumor stemness and tumor immune microenvironment. The qRT-PCR experiments verified the lower expression of IGFBP2 and IGFBP6 in gastric cancer and the lower expression of IGFBP6 in colorectal cancer. Immunohistochemistry validated a marked downregulation of IGFBP2 protein in gastric cancer tissues. The keywords co-occurrence analysis of IGFBP related publications in cancer showed relative research have been more concentrating on the potential of IGFBPs as tumor diagnostic and prognostic markers and developing cancer therapies.

CONCLUSIONS

These findings provide frontier trend of IGFBPs related research and new clues for identifying novel therapeutic targets for various cancers.

The clinical characteristics and prognostic value of IGFBP6 in glioma

BACKGROUND

Glioma is the most common intrinsic tumor in central nervous system and is characterized by their diffuse infiltration of the brain tissue. Insulin-like Growth Factor Binding Protein-6 (IGFBP6) was associated with the insulin-like growth factor binding and insulin-like growth factor II binding processes in many cancers. Herein, we aimed to investigate the biological functions and clinical features of IGFBP6 in gliomas.

METHODS

Totally, we collected 325 RNA sequencing data from CGGA dataset as training cohort, and 969 RNA sequencing data from TCGA dataset as validation cohort. The clinical and molecular characteristics analysis and gene ontology analysis of IGFBP6 were performed. All analyses and graphs were produced based on R language.

RESULTS

We found that IGFBP6 expression was significantly upregulated in GBM patients and downregulated in IDH mutant patients. Receiver Operating Characteristic (ROC) analysis revealed that IGFBP6 could be used as a biomarker to predict TCGA mesenchymal subtype. GO analysis revealed that IGFBP6 was correlated with immunological functions and inflammation activities. Meanwhile, higher expression of IGFBP6 suggested significant relationship with worse prognosis in glioma patients.

CONCLUSIONS

Our findings improved the understanding of IGFBP6 in glioma, and IGFBP6 might be a potential therapeutic target for glioma patients in future clinical trials.

RNA sequencing identified novel target genes for Adansonia digitata in breast and colon cancer cells

Adansonia digitata exhibits numerous beneficial effects. In the current study, we investigated the anti-cancer effects of four different extracts of A. digitata (polar and non-polar extracts of fruit powder and fibers) on the proliferation of human colon cancer (HCT116), human breast cancer (MCF-7), and human ovarian cancer (OVCAR-3 and OVCAR-4) cell lines. RNA sequencing revealed the influence of the effective A. digitata fraction on the gene expression profiles of responsive cells. The results indicated that only the polar extract of the A. digitata fibers exhibited anti-proliferative activities against HCT116 and MCF-7 cells, but not ovarian cancer cells. Moreover, the polar extract of the fibers resulted in the modulation of the expression of multiple genes in HCT116 and MCF-7 cells. We propose that casein kinase 2 alpha 3 (CSNK2A3) is a novel casein kinase 2 (CSNK2) isoform in HCT116 cells and report, for the first time, the potential involvement of FYVE, RhoGEF, and PH domain-containing 3 (FGD3) in colon cancer. Together, these findings provide evidence supporting the anti-cancer potential of the polar extract of A. digitata fibers in this experimental model of breast and colon cancers.

Effect of the Expression of ELOVL5 and IGFBP6 Genes on the Metastatic Potential of Breast Cancer Cells

Breast cancer (BC) is the leading cause of death from malignant neoplasms among women worldwide, and metastatic BC presents the biggest problems for treatment. Previously, it was shown that lower expression of ELOVL5 and IGFBP6 genes is associated with a higher risk of the formation of distant metastases in BC. In this work, we studied the change in phenotypical traits, as well as in the transcriptomic and proteomic profiles of BC cells as a result of the stable knockdown of ELOVL5 and IGFBP6 genes. The knockdown of ELOVL5 and IGFBP6 genes was found to lead to a strong increase in the expression of the matrix metalloproteinase (MMP) MMP1. These results were in good agreement with the correlation analysis of gene expression in tumor samples from patients and were additionally confirmed by zymography. The knockdown of ELOVL5 and IGFBP6 genes was also discovered to change the expression of a group of genes involved in the formation of intercellular contacts. In particular, the expression of the CDH11 gene was markedly reduced, which also complies with the correlation analysis. The spheroid formation assay showed that intercellular adhesion decreased as a result of the knockdown of the ELOVL5 and IGFBP6 genes. Thus, the obtained data indicate that malignant breast tumors with reduced expression of the ELOVL5 and IGFBP6 genes can metastasize with a higher probability due to a more efficient invasion of tumor cells.

Decreased expression of IGFBP6 correlates with poor survival in colorectal cancer patients

BACKGROUND

The insulin-like growth factor binding protein 6 (IGFBP6), as a specific inhibitor of IGF-Ⅱ, is a candidate human anti-oncogene in multiple tumors. However, the expression of IGFBP6 in colorectal cancer (CRC) and prognostic significance are unclear.

METHODS

In this study, we examined colorectal cancer tissues and adjacent normal tissues to determine the expression levels of IGFBP6 mRNA and protein by quantitative reverse-transcription polymerase chain reaction and tissue microarray immunohistochemistry analysis respectively. Moreover, we explored the effects of IGFBP6 on cell growth, migration and invasion by Cell Counting Kit-8(CCK8), colony formation and transwell migration assays. We also investigated whether IGFBP6 expression in tumor tissue correlated with various clinical parameters, including overall survival by univariate and multivariate analyses RESULTS: Both IGFBP6 mRNA and protein levels were significantly lower in colorectal cancer tissues than in adjacent normal colon. Downregulating IGFBP6 using RNAi increased CRC cell proliferation, migration and invasion. Low IGFBP6 expression correlated with poor overall survival in both univariate and multivariate analyses.

CONCLUSION

Our data suggest that IGFBP6 may act as a tumor suppressor gene in the development of CRC, and that low IGFBP6 expression could be used as an independent prognostic biomarker in CRC.

Screening and identification of key biomarkers in nasopharyngeal carcinoma: Evidence from bioinformatic analysis

As for the lack of simple and effective diagnostic methods at the early of the nasopharyngeal carcinoma (NPC), the mortality rate of NPC still remains high. Therefore, it is meaningful to explore the precise molecular mechanisms involved in the proliferation, carcinogenesis, and recurrence of NPC and thus find an effective diagnostic way and make a better therapeutic strategy.Three gene expression data sets (GSE64634, GSE53819, and GSE12452) were downloaded from Gene Expression Omnibus (GEO) and analyzed using the online tool GEO2R to identify differentially expressed genes (DEGs). Gene ontology functional analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis of the DEGs were performed in Database for Annotation, Visualization and Integrated Discovery. The Search Tool for the Retrieval of Interacting Genes database was used to evaluate the interactions of DEGs and to construct a protein-protein interaction network using Cytoscape software. Hub genes were validated with the cBioPortal database.The overlap among the 3 data sets contained 306 genes were identified to be differentially expressed between NPC and non-NPC samples. A total of 13 genes (DNAAF1, PARPBP, TTC18, GSTA3, RCN1, MUC5AC, POU2AF1, FAM83B, SLC22A16, SPEF2, ERICH3, CCDC81, and IL33) were identified as hub genes with degrees ≥10.The present study was attempted to identify and functionally analyze the DEGs that may be involved in the carcinogenesis or progression of NPC by using comprehensive bioinformatics analyses and unveiled a series of hub genes and pathways. A total of 306 DEGs and 13 hub genes were identified and may be regarded as diagnostic biomarkers for NPC. However, more experimental studies are needed to carried out elucidate the biologic function of these genes results for NPC.

Paracrine recruitment and activation of fibroblasts by c-Myc expressing breast epithelial cells through the IGFs/IGF-1R axis

Fibroblasts are among the most abundant stromal cells in the tumor microenvironment (TME), progressively differentiating into activated, motile, myofibroblast-like, protumorigenic cells referred to as Cancer-Associated Fibroblasts (CAFs). To investigate the mechanisms by which epithelial cells direct this transition, the early stages of tumorigenesis were exemplified by indirect cocultures of WI-38 or human primary breast cancer fibroblasts with human mammary epithelial cells expressing an inducible c-Myc oncogene (MCF10A-MycER). After c-Myc activation, the conditioned medium (CM) of MCF10A-MycER cells significantly enhanced fibroblast activation and mobilization. As this was accompanied by decreased insulin-like growth factor binding protein-6 (IGFBP-6) and increased insulin-like growth factor-1 and IGF-II (IGF-I, IGF-II) in the CM, IGFs were investigated as key chemotactic factors. Silencing IGFBP-6 or IGF-I or IGF-II expression in epithelial cells or blocking Insulin-like growth factor 1 receptor (IGF-1R) activity on fibroblasts significantly altered fibroblast mobilization. Exposure of WI-38 fibroblasts to CM from induced MCF10A-MycER cells or to IGF-II upregulated FAK phosphorylation on Tyr³⁹⁷ , as well as the expression of α-smooth muscle actin (α-SMA), features associated with CAF phenotype and increased cell migratory/invasive behavior. In three-dimensional (3D)-organotypic assays, WI-38 or human primary fibroblasts, preactivated with either CM from MCF10A-MycER cells or IGFs, resulted in a permissive TME that enabled nontransformed MCF10A matrix invasion. This effect was abolished by inhibiting IGF-1R activity. Thus, breast epithelial cell oncogenic activation and stromal fibroblast transition to CAFs are linked through the IGFs/IGF-1R axis, which directly promotes TME remodeling and increases tumor invasion.

IGF-binding proteins

Insulin-like growth factor-binding proteins (IGFBPs) 1-6 bind IGFs but not insulin with high affinity. They were initially identified as serum carriers and passive inhibitors of IGF actions. However, subsequent studies showed that, although IGFBPs inhibit IGF actions in many circumstances, they may also potentiate these actions. IGFBPs are widely expressed in most tissues, and they are flexible endocrine and autocrine/paracrine regulators of IGF activity, which is essential for this important physiological system. More recently, individual IGFBPs have been shown to have IGF-independent actions. Mechanisms underlying these actions include (i) interaction with non-IGF proteins in compartments including the extracellular space and matrix, the cell surface and intracellular space, (ii) interaction with and modulation of other growth factor pathways including EGF, TGF-β and VEGF, and (iii) direct or indirect transcriptional effects following nuclear entry of IGFBPs. Through these IGF-dependent and IGF-independent actions, IGFBPs modulate essential cellular processes including proliferation, survival, migration, senescence, autophagy and angiogenesis. They have been implicated in a range of disorders including malignant, metabolic, neurological and immune diseases. A more complete understanding of their cellular roles may lead to the development of novel IGFBP-based therapeutic opportunities.

Role of IGFBP6 Protein in the Regulation of Epithelial-Mesenchymal Transition Genes

Protein IGFBP6 plays an important role in the pathogenesis of many malignant tumors, including breast cancer. The relationship between IGFBP6 protein and the expression of genes associated with the epithelial-mesenchymal transition is studied. Gene IGFBP6 knockdown does not trigger the epithelial-mesenchymal transition in MDA-MB-231 cells, but modifies significantly the expression of many genes involved in this process. A decrease of IGFBP6 expression can involve a decrease in the expression of N-cadherin and transcription factor Slug.