Interferon-induced transmembrane protein 2 promotes epithelial-mesenchymal transition by activating transforming growth factor-β1/small mother against decapentaplegic 2 signaling in gastric cancer

Interferon-induced transmembrane protein 2 is a prognostic marker in colorectal cancer and promotes its progression by activating the PI3K/AKT pathway

BACKGROUND

Interferon-induced transmembrane protein 2 (IFITM2) is involved in repressing viral infection. This study aim to investigate the expression of IFITM2 in colorectal cancer (CRC) and explore its effect on cell proliferation, migration, and invasion.

METHODS

We analyzed The Cancer Genome Atlas (TCGA) database for IFITM2 expression in colorectal cancer and used western blots to detect IFITM2 protein in specimens and cell lines of colorectal cancers. To assess the association between IFITM2 and clinical features, both univariate and multivariate cox regression analysis were conducted. Kaplan-Meier plots were used in the TCGA database to assess IFITM2 gene expression's prognostic significance. Silencing IFITM2 in SW480 and HCT116 cells was achieved by transient transfection with siRNA. Proliferation of CRCs was examined using Cell Counting Kit-8. The effect of IFITM2 on the migration and invasion of CRC cells was studied using wound healing and transwell assays. Gene set enrichment analysis (GSEA) was used to examine IFITM2-associated pathways and Western blotting was used to confirm it.

RESULTS

IFITM2 was over-expressed in the CRC tissues and cells, with high IFITM2 expression related to the tumor N, M, and pathologic stages. The presence of IFITM2 significantly impacted patient survival in CRC. The proliferation of SW480 and HCT116 cells was suppressed when IFITM2 was silenced, resulting in weakened migration and invasion of CRC cells. GSEA analysis showed that IFITM2 was positively related to the phosphoinositide 3-kinase (PI3K)/AKT pathway, and western blot results confirmed that IFITM2 activated it.

CONCLUSIONS

IFITM2 was over-expressed in CRC and modulated the PI3K/AKT pathway to promote CRC cells proliferation and metastasis.

Role of interferon-induced transmembrane protein family in cancer progression: a special focus on pancreatic cancer

Human interferon-induced transmembrane protein family (IFITMs) consists of five main proteins. IFITM1, IFITM2, and IFITM3 can be induced by interferon, while IFITM5 and IFITM10 are insensitive to interferon. IFITMs has various functions, including well-researched antiviral effects. As a molecule whose expression is significantly increased by interferon in the immune microenvironment, IFITMs has drawn growing interest in recent years for their role in the cancer progression. Unlike antiviral effects, the role and mechanism of IFITMs in cancer progression have not been clearly studied, especially the role and molecular mechanism of IFITMs in pancreatic cancer are rarely reported in the literature. This article focuses on the role and potential mechanism of IFITMs in pancreatic cancer progression by analyzing the function and mechanism of IFITM1-3 in other cancers and conducting bioinformatics analysis using the databases, so as to provide a new target for pancreatic cancer therapy.

Role of IFITM2 in osteogenic differentiation of C3H10T1/2 mesenchymal stem cells

Interferon-inducible transmembrane (IFITM) are a family of small proteins localized to plasma and endolysosomal membranes. Their functions beyond restricting viral entry and replication have been revealed in recent years. IFITM5 is involved in bone mineralization and is an osteogenic cell surface marker. IFITM1 and 3 interact with desmin and myosin, and are involved in myogenic differentiation. This study found upregulation of Ifitm2 during osteogenic differentiation of C3H10T1/2 cells. This positively correlated to the expression of osteogenic differentiation markers Col1a1, Alp, Runx2, and Ocn. Knockdown of Ifitm2 by siRNAs inhibited osteogenic differentiation, calcium deposition, and osteogenic marker expression of C3H10T1/2 cells. The osteoblast transcriptome revealed that knocking down Ifitm2 affected the expression Wnt signaling pathway-related genes, including Wnt family members, their receptors Lrp, Frizzled, and Lgr, and transmembrane molecule Rnf43 that suppresses the Wnt signaling pathway. Luciferase assays indicated enhancement of canonical Wnt signaling pathways by Ifitm2 overexpression. Furthermore, IFITM2 was colocalized in the metaphyseal bone and growth plate of the mouse tibial bone with SP7, a transcription factor essential for osteoblast differentiation and bone formation. These findings reveal a possible novel function and potential mechanisms of Ifitm2 in osteogenic differentiation.

IFN-γ Triggered IFITM2 Expression to Induce Malignant Phenotype in Elderly GBM

Advanced age is an important risk factor for the worse clinical presentation of gliomas, especially glioblastoma (GBM). The tumor microenvironment (TME) in elderly GBM (eGBM) patients is considerably different from that in young ones, which causes the inferior clinical outcome. Based on the data from the Chinese Glioma Genome Atlas RNA sequence (CGGA RNA-seq), the Cancer Genome Atlas RNA array (TCGA RNA-array), and gene set enrichment (GSE) 16011 array sets, the differential genes and function between eGBM (≥ 60 years old) and young GBM (yGBM, 20-60 years old) groups were explored. Immunohistochemistry (IHC) was utilized to depict the abundance of CD8+ cells (the main resource of IFN-γ) and IFITM2 protein expression in GBM samples. Furthermore, reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting (WB) were performed to verify the link between IFN-γ and IFITM2. Moreover, the small-interfering RNA (siRNA) of IFITM2 was used to explore the function of IFITM2 in GBM. Characterized by inflammatory TME and higher IFITM2 expression, eGBM harbored a shorter survival time. Chemotaxis and inflammatory cytokine-related genes were enriched in the eGBM group, with more infiltrative CD8+ T cells. The IHC of CD8 and IFITM2-staining could demonstrate these results. In addition, the IFN-γ response pathway was activated in eGBM and resulted in a dismal outcome. Next, it was found that IFITM2 triggered by IFN-γ played a key role in IFN-γ-induced malignant phenotype in eGBM.

Single-cell analysis reveals altered tumor microenvironments of relapse- and remission-associated pediatric acute myeloid leukemia

Acute myeloid leukemia (AML) microenvironment exhibits cellular and molecular differences among various subtypes. Here, we utilize single-cell RNA sequencing (scRNA-seq) to analyze pediatric AML bone marrow (BM) samples from diagnosis (Dx), end of induction (EOI), and relapse timepoints. Analysis of Dx, EOI scRNA-seq, and TARGET AML RNA-seq datasets reveals an AML blasts-associated 7-gene signature (CLEC11A, PRAME, AZU1, NREP, ARMH1, C1QBP, TRH), which we validate on independent datasets. The analysis reveals distinct clusters of Dx relapse- and continuous complete remission (CCR)-associated AML-blasts with differential expression of genes associated with survival. At Dx, relapse-associated samples have more exhausted T cells while CCR-associated samples have more inflammatory M1 macrophages. Post-therapy EOI residual blasts overexpress fatty acid oxidation, tumor growth, and stemness genes. Also, a post-therapy T-cell cluster associated with relapse samples exhibits downregulation of MHC Class I and T-cell regulatory genes. Altogether, this study deeply characterizes pediatric AML relapse- and CCR-associated samples to provide insights into the BM microenvironment landscape.

Molecular cloning, expression and anti-tumor function analysis of yak IFITM2 gene

IFITM2 is interferon-induced transmembrane protein 2, which plays an extremely key role in anti-tumor and anti-virus diseases. In this study, the 602 bp cDNA sequence of the yak (Bos grunniens) IFITM2 (BgIFITM2) gene was obtained. Moreover, the prokaryotic expression vector of BgIFITM2 protein was constructed and expressed successfully, with a molecular weight of 33.680 kDa. The proliferation activities and migration abilities of HepG2 cells were significantly inhibited after treatment with BgIFITM2 protein (0.1 and 1 μg/mL) (P < 0.05). The expressions of B cell lymphoma-2 (BCL2)/BCL2-associated X (BAX) and molecular target of rapamycin (mTOR) genes were significantly decreased, but the expressions of BAX gene were significantly increased after treatment with BgIFITM2 protein (0.1 and 1 μg/mL) (P < 0.05). The expression of BAX protein was also significantly increased after treatment with 1 μg/mL BgIFITM2 protein (P < 0.05). Finally, the addition of BgIFITM2 protein attenuated the formation of tumor lesions in mice, and the pathological damage of the lung was less than that in the model group. The expression of Ki67 protein in the model group was significantly higher than that in the control group (P < 0.05), but the expression of Ki67 protein in the BgIFITM2 group was significantly lower than that in the model group (P < 0.05). Taken together, BgIFITM2 protein could inhibit the proliferative activity of HepG2 cells by regulating apoptosis-related genes, and reduce the invasiveness of HepG2 cells in mice lung tissue. These results facilitate further studies on the function of BgIFITM2 protein.