IFITM3 knockdown reduces the expression of CCND1 and CDK4 and suppresses the growth of oral squamous cell carcinoma cells

Dual Inhibition of CDK4/6 and XPO1 Induces Senescence With Acquired Vulnerability to CRBN-Based PROTAC Drugs

BACKGROUND & AIMS

Despite the increasing number of treatment options available for liver cancer, only a small proportion of patients achieve long-term clinical benefits. Here, we aim to develop new therapeutic approaches for liver cancer.

METHODS

A compound screen was conducted to identify inhibitors that could synergistically induce senescence when combined with cyclin-dependent kinase (CDK) 4/6 inhibitor. The combination effects of CDK4/6 inhibitor and exportin 1 (XPO1) inhibitor on cellular senescence were investigated in a panel of human liver cancer cell lines and multiple liver cancer models. A senolytic drug screen was performed to identify drugs that selectively killed senescent liver cancer cells.

RESULTS

The combination of CDK4/6 inhibitor and XPO1 inhibitor synergistically induces senescence of liver cancer cells in vitro and in vivo. The XPO1 inhibitor acts by causing accumulation of RB1 in the nucleus, leading to decreased E2F signaling and promoting senescence induction by the CDK4/6 inhibitor. Through a senolytic drug screen, cereblon (CRBN)-based proteolysis targeting chimera (PROTAC) ARV-825 was identified as an agent that can selectively kill senescent liver cancer cells. Up-regulation of CRBN was a vulnerability of senescent liver cancer cells, making them sensitive to CRBN-based PROTAC drugs. Mechanistically, we find that ubiquitin specific peptidase 2 (USP2) directly interacts with CRBN, leading to the deubiquitination and stabilization of CRBN in senescent liver cancer cells.

CONCLUSIONS

Our study demonstrates a striking synergy in senescence induction of liver cancer cells through the combination of CDK4/6 inhibitor and XPO1 inhibitor. These findings also shed light on the molecular processes underlying the vulnerability of senescent liver cancer cells to CRBN-based PROTAC therapy.

Exploring the anti-atherosclerosis mechanism of ginsenoside Rb1 by integrating network pharmacology and experimental verification

Ginsenoside Rb1 is the major active constituent of ginseng, which is widely used in traditional Chinese medicine for the atherosclerosis treatment by anti-inflammatory, anti-oxidant and reducing lipid accumulation. We explored cellular target and molecular mechanisms of ginsenoside Rb1 based on network pharmacology and in vitro experimental validation. In this study, we predicted 17 potential therapeutic targets for ginsenoside Rb1 with atherosclerosis from public databases. We then used protein-protein interaction network to screen the hub targets. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway enrichment showed that the effects of ginsenoside Rb1 were meditated through multiple targets and pathways. Next, molecular docking results revealed that in the 10 core targets, CCND1 has the highest binding energy with ginsenoside Rb1. Vascular cell proliferation plays a critical role in atherosclerosis development. However, the effect and direct target of ginsenoside Rb1 in regulating vascular cell proliferation in atherosclerosis remains unclear. Edu straining results indicated that ginsenoside Rb1 inhibited the cell proliferation of endothelial cells, macrophages, and vascular smooth muscle cells. The protein immunoprecipitation (IP) analysis showed that ginsenoside Rb1 inhibited the vascular cell proliferation by suppressing the interaction of CCDN1 and CDK4. These findings systematically reveal that the anti-atherosclerosis mechanism of ginsenoside Rb1 by integrating network pharmacology and experimental validation, which provide evidence to treat atherosclerosis by using ginsenoside Rb1 and targeting CCND1.

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.

Upregulation of miR-519d-3p Inhibits Viability, Proliferation, and G1/S Cell Cycle Transition of Oral Squamous Cell Carcinoma Cells Through Targeting CCND1

Background: MicroRNA (miR)-519d-3p suppresses tumor development, however, its role in oral squamous cell carcinoma (OSCC) has yet to be determined. Materials and Methods: OSCC and adjacent tissues were collected (n = 45 for adjacent; n = 21 for Stage I-II OSCC; n = 24 for Stage III-IV OSCC). The cell viability, proliferation, and cell cycle of OSCC were, respectively, assessed by the Cell Counting Kit-8 (CCK-8), colony formation assay, and flow cytometry. Relative expressions of cell cycle-regulated proteins (Cyclin D1 [CCND1], CDK4, and CDK6) and miR-519d-3p were measured with Western blot and quantitative real-time polymerase chain reaction as needed. Dual-luciferase reporter assay was performed to verify the prediction of TargetScan that miR-519d-3p and CCND1 shared potential binding sites. Correlation analysis between miR-519d-3p and CCND1 was performed with Pearson's correlation test. Results: In OSCC tissues, downregulating miR-519d-3p expression correlated with a higher tumor grade. Upregulating miR-519d-3p expression inhibited OSCC cell viability and proliferation, increased cells in G0/G1 phase and reduced those in S/G2 phase, and downregulated the expressions of cell cycle-related protein (CDK4, CDK6). CCND1 was the target gene of miR-519d-3p, and overexpressed CCND1 reversed the effects of upregulation of miR-519d-3p on suppressing the viability, proliferation, and cell cycle of OSCC cells. Conclusions: miR-519d-3p upregulation suppressed the cell viability, proliferation, and G1/S cell cycle transition of OSCC through targeting CCND1. The current findings provide a possible clinical option for OSCC treatment.

Proteomic detection of COX-2 pathway-related factors in patients with adenomyosis

Background

Investigating the relationship between cyclooxygenase-2 (COX-2) pathway-related factors and clinical features in patients with adenomyosis by proteomics could provide potential therapeutic targets.

Methods

This study recruited 40 patients undergoing surgical hysterectomy and pathological diagnosis of adenomyosis, collected ectopic endometrial specimens, and recorded clinical data. The expression levels of COX-2 in ectopic uterus lesions were detected using the immunohistochemical (IHC) SP method. The 40 samples were then divided into a COX-2 low or high expression group. Five samples with the most typical expression levels were selected from each of the two groups and the differential proteins between the two groups were identified using label-free quantitative proteomics. WW domain-binding protein 2 (WBP2), interferon induced transmembrane protein 3 (IFITM3), and secreted frizzled-related protein 4 (SFRP4) were selected for further verification, and their relationships with COX-2 and clinical characteristics were analyzed.

Results

There were statistically significant differences in the expression of WBP2, IFITM3, and SFRP4 between the COX-2 low and high expression groups (P < 0.01). The expressions of COX-2, IFITM3, and SFRP4 were significantly correlated with dysmenorrhea between the two groups (P < 0.05), but not with uterine size or menstrual volume (P > 0.05). However, there was no significant correlation between the expression of WBP2 and dysmenorrhea, uterine size, and menstruation volume in both the high expression and low expression groups (P > 0.05).

Conclusions

COX-2, IFITM3, SFRP4, and WBP2 may be involved in the pathogenesis of adenomyosis. COX-2, IFITM3, and SFRP4 may serve as potential molecular biomarkers or therapeutic targets in dysmenorrhea in patients with early adenomyosis.

IFITM3 promotes glioblastoma stem cell-mediated angiogenesis via regulating JAK/STAT3/bFGF signaling pathway

Interferon-induced transmembrane protein 3 (IFITM3) has been previously verified to be an endosomal protein that prevents viral infection. Recent findings suggested IFITM3 as a key factor in tumor invasion and progression. To clarify the role and molecular mechanism of IFITM3 in Glioblastoma multiforme (GBM) progression, we investigated the expression of IFITM3 in glioma datasets culled from The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA). Primary GBM stem cells (GSCs) were cultured and identified in vitro. Loss-of-function and gain-of-function experiments were established by using shRNAs and lentiviral vectors targeting IFITM3. Co-culture system of GSCs and vascular endothelial cells was constructed in a Transwell chamber. Tube formation and spheroid-based angiogenesis assays were performed to determine the angiogenic capacity of endothelial cells. Results revealed that IFITM3 is elevated in GBM samples and predictive of adverse outcome. Mechanistically, GSCs-derived IFITM3 causes activation of Jak2/STAT3 signaling and leads to robust secretion of bFGF into tumor environment, which eventually results in enhanced angiogenesis. Taken together, these evidence indicated IFITM3 as an essential factor in GBM angiogenesis. Our findings provide a new insight into mechanism by which IFITM3 modulates GBM angiogenesis.

M2 Macrophages-Derived Exosomal miRNA-23a-3p Promotes the Progression of Oral Squamous Cell Carcinoma by Targeting PTEN

Exosomes from tumor cells and immune cells regulate the tumor microenvironment through the biomolecules or microRNAs (miRNAs) they carry. This research aims to investigate the role of miRNA in exosomes derived from tumor-associated macrophages (TAMs) in the progression of oral squamous cell carcinoma (OSCC). RT-qPCR and Western blotting assays were used to determine the expression of genes and proteins in OSCC cells. CCK-8, Scratch assay and invasion-related proteins were utilized to detect the malignant progression of tumor cells. High-throughput sequencing predicted differentially expressed miRNAs in exosomes secreted by M0 and M2 macrophages. Compared with exosomes from M0 macrophages, exosomes from M2 macrophages led to enhanced proliferation and invasion of OSCC cells and inhibited their apoptosis. High-throughput sequencing results show that miR-23a-3p is differentially expressed in exosomes from M0 and M2 macrophages. MiRNA target gene database predicts that phosphatase and tensin homolog (PTEN) are target genes of miR-23a-3p. Further studies revealed that transfection of miR-23a-3p mimics inhibited PTEN expression in vivo and in vitro and promoted the malignant progression of OSCC cells, which was reversed by miR-23a-3p inhibitors. MiR-23a-3p in exosomes derived from M2 macrophages promotes malignant progression of OSCC. PTEN is a potential intracellular target of miR-23a-3p. MiR-23a-3p, an M2 macrophage-associated exosome, is a promising target for the future treatment of OSCC.

IFITM protein regulation and functions: Far beyond the fight against viruses

Interferons (IFNs) are important cytokines that regulate immune responses through the activation of hundreds of genes, including interferon-induced transmembrane proteins (IFITMs). This evolutionarily conserved protein family includes five functionally active homologs in humans. Despite the high sequence homology, IFITMs vary in expression, subcellular localization and function. The initially described adhesive and antiproliferative or pro-oncogenic functions of IFITM proteins were diluted by the discovery of their antiviral properties. The large set of viruses that is inhibited by these proteins is constantly expanding, as are the possible mechanisms of action. In addition to their beneficial antiviral effects, IFITM proteins are often upregulated in a broad spectrum of cancers. IFITM proteins have been linked to most hallmarks of cancer, including tumor cell proliferation, therapeutic resistance, angiogenesis, invasion, and metastasis. Recent studies have described the involvement of IFITM proteins in antitumor immunity. This review summarizes various levels of IFITM protein regulation and the physiological and pathological functions of these proteins, with an emphasis on tumorigenesis and antitumor immunity.

Studies on Chemical Composition of Pueraria lobata and Its Anti-Tumor Mechanism

Fourteen compounds were isolated from Pueraria lobata (Willd.) Ohwi by column chromatography and preparative thin-layer chromatography; the structures were identified by spectroscopic analysis and compared with data reported in the literature. Seven compounds were isolated and identified from Pueraria lobata for the first time: Linoleic acid, Sandwicensin, Isovanillin, Ethyl ferulate, Haginin A, Isopterofuran, 3′.7-Dihydroxyisoflavan. The other 10 compounds were structurally identified as follows: Lupenone, Lupeol, β-sitosterol, Genistein, Medicarpin, Coniferyl Aldehyde, Syringaldehyde. All compounds were evaluated for their ability to inhibit SW480 and SW620 cells using the CCK-8 method; compound 5 (Sandwicensin) had the best activity, and compounds 6, 9, 11 and 12 exhibited moderate inhibitory activity. In addition, the targets and signaling pathways of Sandwicensin treatment for CRC were mined using network pharmacology, and MAPK3, MTOR, CCND1 and CDK4 were found to be closely associated with Sandwicensin treatment for CRC; the GO and KEGG analysis showed that Sandwicensin may directly regulate the cycle, proliferation and apoptosis of CRC cells through cancer-related pathways.

Comparative Proteomic Profiling of Ectosomes Derived from Thyroid Carcinoma and Normal Thyroid Cells Uncovers Multiple Proteins with Functional Implications in Cancer

Proteins carried by tumor-derived ectosomes play an important role in cancer progression, and are considered promising diagnostic markers. In the present study, a shotgun nanoLC–MS/MS proteomic approach was applied to profile and compare the protein content of ectosomes released in vitro by normal human thyroid follicular epithelial Nthy-ori 3-1 cells and human anaplastic thyroid carcinoma (TC) 8305C cells. Additionally, the pro-migratory and pro-proliferative effects of Nthy-ori 3-1- and 8305C-derived ectosomes exerted on the recipient cells were assessed in wound closure and Alamar Blue assays. A total of 919 proteins were identified in all replicates of 8305C-derived ectosomes, while Nthy-ori 3-1-derived ectosomes contained a significantly lower number of 420 identified proteins. Qualitative analysis revealed 568 proteins present uniquely in 8305C-derived ectosomes, suggesting their applicability in TC diagnosis and management. In addition, 8305C-derived ectosomes were able to increase the proliferation and motility rates of the recipient cells, likely due to the ectosomal transfer of the identified cancer-promoting molecules. Our description of ectosome protein content and its related functions provides the first insight into the role of ectosomes in TC development and progression. The results also indicate the applicability of some of these ectosomal proteins for further investigation regarding their potential as circulating TC biomarkers.

Proteomic Analysis of Hypoxia-Induced Senescence of Human Bone Marrow Mesenchymal Stem Cells

Methods

Hypoxia in hBMSCs was induced for 0, 4, and 12 hours, and cellular senescence was evaluated by senescence-associated β-galactosidase (SA-β-gal) staining. Tandem mass tag (TMT) labeling was combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) for differential proteomic analysis of hypoxia in hBMSCs. Parallel reaction monitoring (PRM) analysis was used to validate the candidate proteins. Verifications of signaling pathways were evaluated by western blotting. Cell apoptosis was evaluated using Annexin V/7-AAD staining by flow cytometry. The production of reactive oxygen species (ROS) was detected by the fluorescent probe 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA).

Results

Cell senescence detected by SA-β-gal activity was higher in the 12-hour hypoxia-induced group. TMT analysis of 12-hour hypoxia-induced cells identified over 6000 proteins, including 686 differentially expressed proteins. Based on biological pathway analysis, we found that the senescence-associated proteins were predominantly enriched in the cancer pathways, PI3K-Akt pathway, and cellular senescence signaling pathways. CDK1, CDK2, and CCND1 were important nodes in PPI analyses. Moreover, the CCND1, UQCRH, and COX7C expressions were verified by PRM. Hypoxia induction for 12 hours in hBMSCs reduced CCND1 expression but promoted ROS production and cell apoptosis. Such effects were markedly reduced by the PI3K agonist, 740 Y-P, and attenuated by LY294002.

Conclusions

Hypoxia of hBMSCs inhibited CCND1 expression but promoted ROS production and cell apoptosis through activating the PI3K-dependent signaling pathway. These findings provided a detailed characterization of the proteomic profiles related to hypoxia-induced senescence of hBMSCs and facilitated our understanding of the molecular mechanisms leading to stem cell senescence.

Interferon-Induced Transmembrane Protein 3 Shapes an Inflamed Tumor Microenvironment and Identifies Immuno-Hot Tumors

Interferon-induced transmembrane protein 3 (IFITM3) is an interferon-induced membrane protein, which has been identified as a functional gene in multiple human cancers. The role of IFITM3 in cancer has been preliminarily summarized, but its relationship to antitumor immunity is still unclear. A pancancer analysis was conducted to investigate the expression pattern and immunological role of IFITM3 based on transcriptomic data downloaded from The Cancer Genome Atlas (TCGA) database. Next, correlations between IFITM3 and immunological features in the bladder cancer (BLCA) tumor microenvironment (TME) were assessed. In addition, the role of IFITM3 in estimating the clinical characteristics and the response to various therapies in BLCA was also evaluated. These results were next confirmed in the IMvigor210 cohort and a recruited cohort. In addition, correlations between IFITM3 and emerging immunobiomarkers, such as microbiota and N6-methyladenosine (m6A) genes, were assessed. IFITM3 was enhanced in most tumor tissues in comparison with adjacent tissues. IFITM3 was positively correlated with immunomodulators, tumor-infiltrating immune cells (TIICs), cancer immunity cycles, and inhibitory immune checkpoints. In addition, IFITM3 was associated with an inflamed phenotype and several established molecular subtypes. IFITM3 expression also predicted a notably higher response to chemotherapy, anti-EGFR therapy, and immunotherapy but a low response to anti-ERBB2, anti-ERBB4, and antiangiogenic therapy. In addition, IFITM3 was correlated with immune-related microbiota and m6A genes. In addition to BLCA, IFITM3 is expected to be a marker of high immunogenicity in most human cancers. In conclusion, IFITM3 expression can be used to identify immuno-hot tumors in most cancers, and IFITM3 may be a promising pancancer biomarker to estimate the immunological features of tumors.

Molecular characterization, expression and functional analysis of yak IFITM3 gene

IFITM3 is interferon-induced transmembrane 3, which plays an extremely key role in anti-proliferation, anti-virus and anti-tumor diseases. In this study, the yak (Bos grunniens) IFITM3 (BgIFITM3) gene contained a 5'-untranslated region (UTR) (25 bp), a coding region (441 bp), and a 3'-UTR (115 bp). The expression of BgIFITM3 gene in liver was significantly higher than that in heart, spleen, lung and kidney (P < 0.01). BgIFITM3 protein was localized on the yak hepatocyte plasma membrane, and its expression was significantly different between 1 day and 15 months of age (P < 0.05). Moreover, the prokaryotic expression vector of BgIFITM3 protein was constructed and expressed successfully, with a molecular weight of 19.5 kDa. The activities of yak hepatocyte were significantly inhibited after treating with BgIFITM3 protein (10 and 20 μg/mL) (P < 0.01). The expression levels of ERBB-2, IRS-1, PI3KR-1, AKT-1 and MAPK-3 were significantly lower after treating with 20 μg/mL BgIFITM3 protein (P < 0.05). Besides, the activities of HepG2 cells were significantly inhibited after treating with BgIFITM3 protein (1, 10 and 20 μg/mL) (P < 0.05). While, the cloning ability and migration ability of HepG2 cells were significantly inhibited after treating with 10 μg/mL BgIFITM3 protein (P < 0.05). Finally, the mitochondria of HepG2 cells was concentrated, cristae widened, and the double film density of mitochondria was increased after treating with 10 μg/mL BgIFITM3 protein. After 10 μg/mL BgIFITM3 protein treating, the expression levels of VDAC-2, VDAC-3 and p53 genes were significantly increased, but the expression level of GPX-4 gene was significantly decreased (P < 0.01). Taken together, the BgIFITM3 protein could inhibit the proliferations of yak hepatocyte and HepG2 cells by regulating the PI3K/Akt pathway or ferroptosis-related genes, respectively. These results benefit for further study of the function of BgIFITM3 protein.

Circ_0000745 strengthens the expression of CCND1 by functioning as miR-488 sponge and interacting with HuR binding protein to facilitate the development of oral squamous cell carcinoma

BACKGROUND

The implication of circular RNAs (circRNAs) in human cancers has aroused much concern. In this study, we investigated the function of circ_0000745 and its potential functional mechanisms in oral squamous cell carcinoma (OSCC) to further understand OSCC pathogenesis.

METHODS

The expression of circ_0000745, miR-488 and cyclin D1 (CCND1) mRNA was measured by quantitative real-time polymerase chain reaction (qPCR). Cell proliferation capacity was assessed by cell counting kit-8 (CCK-8) assay and colony formation assay. Cell cycle progression and cell apoptosis were determined by flow cytometry assay. The protein levels of CCND1, PCNA, Cleaved-caspase 3 and HuR were detected by western blot. Animal study was conducted to identify the role of circ_0000745 in vivo. The targeted relationship was verified by dual-luciferase reporter assay, pull-down assay or RNA immunoprecipitation (RIP) assay.

RESULTS

The expression of circ_0000745 was increased in OSCC tissues and cells. Circ_0000745 downregulation inhibited OSCC cell proliferation and induced cell cycle arrest and apoptosis in vitro, as well as blocked tumor growth in vivo. MiR-488 was a target of circ_0000745, and circ_0000745 downregulation suppressed OSCC development by enriching miR-488. Besides, circ_0000745 regulated CCND1 expression by targeting miR-488. In addition, circ_0000745 regulated CCND1 expression by interacting with HuR protein. CCND1 knockdown also inhibited OSCC cell proliferation and induced cell cycle arrest and apoptosis in vitro, and CCND1 overexpression recovered the inhibitory effects on OSCC cell malignant behaviors caused by circ_0000745 downregulation.

CONCLUSIONS

Circ_0000745 regulated the expression of CCND1 partly by acting as miR-488 sponge and interacting with HuR protein, thus promoting the progression of OSCC.

Integrative Analysis of TP53INP2 in Head and Neck Squamous Cell Carcinoma

TP53INP2 plays an important role in regulating gene transcription and starvation-induced autophagy, however, its function in head and neck squamous cell carcinoma (HNSCC) remains unclear. Therefore, we assessed the expression and prognostic value of TP53INP2. In addition, RNAseq, miRNAseq, copy number variation, and mutation profiles from The Cancer Genome Atlas (TCGA) dataset were applied to evaluate the distinctive genomic patterns related to TP53INP2 expression. We found that TP53INP2 expression was lower in HNSCC compared with normal controls. Patients with higher TP53INP2 expression had longer survival time. Knockdown of TP53INP2 promoted cell viability. Functional analysis exhibited that TP53INP2 was linked to DNA replication, DNA repair, cell cycle, and multiple metabolic pathways. Moreover, TP53INP2 might affect the expression of multiple genes via enhancing the transcriptional activity of nuclear hormone receptors. A competing endogenous RNA (ceRNA) network consisting of 33 lncRNAs, eight miRNAs, and 13 mRNAs was constructed based on the expression of TP53INP2. Taken together, our study highlights the potential value of TP53INP2 in predicting the survival of HNSCC and its important role in the genesis and development of HNSCC.

Identification of E2F transcription factor 7 as a novel potential biomarker for oral squamous cell carcinoma

BACKGROUND

As a tumor-accelerating transcriptional factor, E2F transcription factor 7 (E2F7) was up-regulated in many forms of cancers. Nevertheless, little has been reported about the impacts of E2F7 on oral squamous cell carcinoma (OSCC). Here, we aimed to probe whether E2F7 had influences on OSCC and its potential mechanism.

METHODS

The expression of E2F7 in OSCC tissues was analyzed using the data acquired from TCGA and ONCOMINE databases. E2F7 prognostic value in OSCC patients was analyzed utilizing TCGA database. The expression of E2F7 in OSCC cell lines was detected by qRT-PCR. Gain-and loss-function of E2F7 assays in TCA-83 and CAL27 cells were performed respectively to inquire the function of E2F7. Western blotting was applied to test the alternations of EMT-related markers.

RESULTS

In OSCC tissues, E2F7 was highly expressed. Besides, high expression of E2F7 predicted worse prognosis in OSCC patients. Moreover, E2F7 was over-expressed in TCA-83, HSC-4 and CAL27 (all OSCC cell lines) cells relative to that in HNOK (a normal cell line) cells. Gain-and loss-function assays displayed that deficiency of E2F7 suppresses CAL27 cell growth, migration, invasion and E2F7 high-expression resulted in inverse outcomes in TCA-83 cells. Finally, we found that silencing of E2F7 facilitated E-cadherin protein expression level and reduced N-cadherin, Vimentin and Snail protein levels in CAL27 cells, whilst E2F7 high-expression exhibited the opposite effects in TCA-83 cells.

CONCLUSIONS

These outcomes indicated that E2F7 performs a carcinogenic role in OSCC, which provides a theoretical basis for the therapeutic strategies of OSCC.

Silencing of LncRNA SNHG16 Downregulates Cyclin D1 (CCND1) to Abrogate Malignant Phenotypes in Oral Squamous Cell Carcinoma (OSCC) Through Upregulating miR-17-5p

Background

Targeting the long non-coding RNAs (LncRNAs)-microRNAs (miRNAs)-mRNA competing endogenous RNA (ceRNA) networks has been proved as an effective strategy to treat multiple cancers, including oral squamous cell carcinoma (OSCC). Based on this, the present study identified a novel LncRNA SNHG16/miR-17-5p/CCND1 signaling pathway that played an important role in regulating the pathogenesis of OSCC.

Methods

The expression levels of cancer-associated genes were examined by Real-Time qPCR and Western Blot at transcriptional and translated levels, respectively. CCK-8 assay was performed to determine cell proliferation, and cell apoptosis ratio was measured by the Annexin V-FITC/PI double staining assay. Transwell assay was performed to examine cell migration, and dual-luciferase reporter gene system assay was used to validate the ceRNA networks.

Results

LncRNA SNHG16 and CCND1 were upregulated, while miR-17-5p was downregulated in OSCC tissues and cell lines, compared to their normal counterparts. Also, miR-17-5p negatively correlated with both LncRNA SNHG16 and CCND1 mRNA, but LncRNA SNHG16 was positively relevant to CCND1 mRNA in OSCC tissues. By performing the gain- and loss-of-function experiments, we noticed that LncRNA SNHG16 overexpression aggravated the malignant phenotypes, such as cell proliferation, viability, migration and epithelial-mesenchymal transition (EMT) in OSCC cells, while LncRNA SNHG16 knock-down had opposite effects. Furthermore, our dual-luciferase reporter gene system evidenced that LncRNA SNHG16 sponged miR-17-5p to upregulate CCND1 in OSCC cells, and the inhibiting effects of LncRNA SNHG16 ablation on OSCC progression were abrogated by both downregulating miR-17-5p and overexpressing CCND1. Finally, the xenograft tumor-bearing mice models were established, and our data validated that LncRNA SNHG16 served as an oncogene to promote tumorigenicity of OSCC cells in vivo.

Conclusion

Taken together, targeting the LncRNA SNHG16/miR-17-5p/CCND1 axis hindered the development of OSCC, and this study provided potential diagnostic and therapeutic biomarkers for OSCC in clinic.

Iron Oxide Nanoparticles Combined with Cytosine Arabinoside Show Anti-Leukemia Stem Cell Effects on Acute Myeloid Leukemia by Regulating Reactive Oxygen Species

BACKGROUND AND AIM

Acute myeloid leukemia (AML), initiated and maintained by leukemia stem cells (LSCs), is often relapsed or refractory to therapy. The present study aimed at assessing the effects of nanozyme-like Fe3O4 nanoparticles (IONPs) combined with cytosine arabinoside (Ara-C) on LSCs in vitro and in vivo.

METHODS

The CD34+CD38-LSCs, isolated from human AML cell line KG1a by a magnetic activated cell sorting method, were treated with Ara-C, IONPs, and Ara-C+ IONPs respectively in vitro. The cellular proliferation, apoptosis, reactive oxygen species (ROS), and the related molecular expression levels in LSCs were analyzed using flow cytometry, RT-qPCR, and Western blot. The nonobese diabetic/severe combined immune deficiency mice were transplanted with LSCs or non-LSCs via tail vein, and then the mice were treated with Ara-C, IONPs and IONPs plus Ara-C, respectively. The therapeutic effects on the AML bearing mice were further evaluated.

RESULTS

LSCs indicated stronger cellular proliferation, more clone formation, and more robust resistance to Ara-C than non-LSCs. Compared with LSCs treated with Ara-C alone, LSCs treated with IONPs plus Ara-C showed a significant increase in apoptosis and ROS levels that might be regulated by nanozyme-like IONPs via improving the expression of pro-oxidation molecule gp91-phox but decreasing the expression of antioxidation molecule superoxide dismutase 1. The in vivo results suggested that, compared with the AML bearing mice treated with Ara-C alone, the mice treated with IONPs plus Ara-C markedly reduced the abnormal leukocyte numbers in peripheral blood and bone marrow and significantly extended the survival of AML bearing mice.

CONCLUSION

IONPs combined with Ara-C showed the effectiveness on reducing AML burden in the mice engrafted with LSCs and extending mouse survival by increasing LSC's ROS level to induce LSC apoptosis. Our findings suggest that targeting LSCs could control the AML relapse by using IONPs plus Ara-C.

Malignancy and IFITM3: Friend or Foe?

The prevalence and incidence of cancers has risen over the last decade. Available treatments have improved outcomes, yet mortality and morbidity remain high, creating an urgent demand for personalized and new therapy targets. Interferon induced transmembrane protein (IFITM3) is highly expressed in cancers and is a marker of poor prognosis. In this review, we discuss recent advances in IFITM3 biology, the regulatory pathways, and its function within cancer as part of immunity and maintaining stemness. Overexpression of IFITM3 is likely an indirect effect of ongoing inflammation, immune and cancer epithelial-to-mesenchymal (EMT) related pathways i.e., interferons, TGF-β, WNT/β-catenin, etc. However, IFITM3 also influences tumorigenic phenotypes, such as cell proliferation, migration and invasion. Furthermore, IFITM3 plays a key role in cancer growth and maintenance. Silencing of IFITM3 reduces these phenotypes. Therefore, targeting of IFITM3 will likely have implications for potential cancer therapies.

Noncoding RNAs in oral premalignant disorders and oral squamous cell carcinoma

BACKGROUND

Oral squamous cell carcinoma (OSCC) has the highest mortality rate among all head and neck cancers and a relatively low five-year survival rate. Generally, the development of an oral mucosal malignancy represents a multistep process beginning with normal oral mucosa epithelium and culminating in OSCC after transitioning through intermediary oral premalignant disorders (OPMDs), during which dysplasia is often observed. Noncoding RNAs (ncRNAs) are RNAs that are not translated into proteins, but still can participate in regulating neoplastic cell behavior. Recently, data have emerged on the role of ncRNAs in the progression of oral mucosal malignant diseases, but the exact mechanisms through which ncRNAs are involved remain to be elucidated.

CONCLUSIONS

Knowledge on ncRNAs has added an extra layer of complexity to our understanding of the malignant progression of oral mucosal diseases. The identification of ncRNAs in multiple body fluids as biomarkers may provide new diagnostic options that can be used for the diagnosis and prognosis of OPMDs and OSCC, respectively. Despite overall advances that have been made in cancer treatment, the treatment options for OPMDs and OSCC are still limited. Several studies have shown that ncRNA-based treatment regimens may hold promise as alternative methods for treating OPMDs and OSCC. The use of ncRNAs as therapeutic agents, including miR-155, miR-34 and lncRNA HOTAIR, appear promising.

miR‑296‑3p promotes the proliferation of glioblastoma cells by targeting ICAT

MicroRNAs (miRNA/miRs) serve an important function in the regulation of gene expression, and have been indicated to mediate a number of cellular biological processes, including cell proliferation, the cell cycle, cell apoptosis and cell differentiation. The altered expression of miRNAs has been revealed to result in a variety of human diseases, including glioblastoma multiforme (GBM). The present study indicated an increase in miR‑296‑3p in glioma tumor types compared with normal brain, particularly in the samples from patients with high grade GBM. Antagonizing miR‑296‑3p was demonstrated to induce cell growth arrest and cell cycle redistribution in U251 cells. The miR‑296‑3p antagonist altered the expression of a number of key genes that are involved in cell cycle control, including cyclin D1 and p21. Additionally, the decrease of miR‑296‑3p increased inhibitor of β‑catenin and T cell factor (ICAT) expression, and increased miR‑296‑3p‑inhibited ICAT expression in U251 cells. Bioinformatics analysis indicated that ICAT is a target gene of miR‑296‑3p, which was further validated using a dual‑luciferase reporter assay. Through the regulation of ICAT, the miR‑296‑3p antagonist decreased β‑catenin protein expression and increased the expression of its target genes. Silencing ICAT was indicated to reverse the miR‑296‑3p downregulation‑induced inactivation of Wnt signaling and cell growth arrest in glioma cells. The present study also indicated a negative correlation between ICAT mRNA levels and miR‑296‑3p levels in glioma tumor types. In conclusion, the present study identified an oncogenic function of miR‑296‑3p in glioblastoma via the direct regulation of ICAT.

IFITM3/STAT3 axis promotes glioma cells invasion and is modulated by TGF-β

Glioma is the most aggressive primary brain tumor. We have previously provided evidence that IFITM3 promoted glioma cells migration. However, the mechanism of how IFITM3 regulates glioma cells invasion and whether IFITM3 participates in TGF-β-mediated glioma invasion are still unknown. In this paper, we proved that IFITM3 was notably up-regulated in glioma tissues. Knockdown of IFITM3 suppressed STAT3 phosphorylation in vitro, and a specific STAT3 inhibitor AG490 reversed IFITM3-induced invasion of glioma cells. Furthermore, IFITM3 expression was induced by TGF-β in glioma and IFITM3 knockdown abolished TGF-β-mediated glioma cells invasion. Collectively, the results indicate that IFITM3/STAT3 axis may promote TGF-β-induced glioma cells invasion. This study provided some suggestions for the clinical treatment of the brain tumor.

Identification of AUNIP as a candidate diagnostic and prognostic biomarker for oral squamous cell carcinoma

Background

Oral squamous cell carcinoma (OSCC) is one of the most common malignant tumors worldwide. Patients with poorly differentiated OSCC often exhibit a poor prognosis. AUNIP (Aurora Kinase A and Ninein Interacting Protein), also known as AIBp, plays a key role in cell cycle and DNA damage repair. However, the function of AUNIP in OSCC remains elusive.

Methods

The differentially expressed genes (DEGs) were obtained using R language. Receiver operating characteristic curve analysis was performed to identify diagnostic markers for OSCC. The effectiveness of AUNIP in diagnosing OSCC was evaluated by machine learning. AUNIP expression was analyzed in publicly available databases and clinical specimens. Bioinformatics analysis and in vitro experiments were conducted to explore biological functions and prognostic value of AUNIP in OSCC.

Findings

The gene integration analysis revealed 90 upregulated DEGs. One candidate biomarker, AUNIP, for the diagnosis of OSCC was detected, and its expression gradually increased along with malignant differentiation of OSCC. Bioinformatics analysis demonstrated that AUNIP could be associated with tumor microenvironment, human papillomavirus infection, and cell cycle in OSCC. The suppression of AUNIP inhibited OSCC cell proliferation and resulted in G0/G1 phase arrest in OSCC cells. The survival analysis showed that AUNIP overexpression predicted poor prognosis of OSCC patients.

Interpretation: AUNIP could serve as a candidate diagnostic and prognostic biomarker for OSCC and suppression of AUNIP may be a potential approach to preventing and treating OSCC.

Fund

Taishan Scholars Project in Shandong Province (ts201511106) and the National Natural Science Foundation of China (Nos. 61603218).