Comprehensive analysis of DTYMK in pan-cancer and verification in lung adenocarcinoma.

Previous documents have reported that the deoxythymidylate kinase (DTYMK) genes were involved in the progression of cancers. However, its significance in the analysis of pan-cancer and specific molecular mechanism were still poorly understood. In the present study, we conducted a comprehensive study of the DTYMK gene associated with its clinical relevance across a broad-spectrum of human tumors. In addition, association among DTYMK gene and tumor immunogenic features was also explored. Considering the results of pan-cancer analysis, the specific tumor lung adenocarcinoma (LUAD) was chosen to further study the DTYMK-induced signaling pathways and intercellular communications in tumor progression. Our findings demonstrated that DTYMK may be a new biomarker for the prognosis and immunotherapy in various cancers. Importantly, DTYMK was expected to be a guiding marker gene for clinical prognosis and tumor personalized therapy in LUAD.

RASSF1A inhibits PDGFB-driven malignant phenotypes of nasopharyngeal carcinoma cells in a YAP1-dependent manner.

Nasopharyngeal carcinoma (NPC) is a highly aggressive tumor characterized by distant metastasis. Deletion or down-regulation of the tumor suppressor protein ras-association domain family protein1 isoform A (RASSF1A) has been confirmed to be a key event in NPC progression; however, little is known about the effects or underlying mechanism of RASSF1A on the malignant phenotype. In the present study, we observed that RASSF1A expression inhibited the malignant phenotypes of NPC cells. Stable silencing of RASSF1A in NPC cell lines induced self-renewal properties and tumorigenicity in vivo/in vitro and the acquisition of an invasive phenotype in vitro. Mechanistically, RASSF1A inactivated Yes-associated Protein 1 (YAP1), a transcriptional coactivator, through actin remodeling, which further contributed to Platelet Derived Growth Factor Subunit B (PDGFB) transcription inhibition. Treatment with ectopic PDGFB partially increased the malignancy of NPC cells with transient knockdown of YAP1. Collectively, these findings suggest that RASSF1A inhibits malignant phenotypes by repressing PDGFB expression in a YAP1-dependent manner. PDGFB may serve as a potential interest of therapeutic regulators in patients with metastatic NPC.

Prognostic value of immune cell infiltration in bladder cancer: A gene expression-based study.

The present study aimed to analyse the relationship between tumour-infiltrating immune cells (TIICs) and the prognosis of bladder cancer (BC). In the present study, an established computational method (CIBERSORT) was used to analyse the gene expression profile of BC from 409 patients to infer the number of infiltrating immune cells among 22 immune cell subsets. The relationship between each cell type and overall survival (OS) was further analysed. Single-sample GSEA and ESTIMATE algorithms were performed to evaluate the composition of immune microenvironment in each immune cluster. A significant difference in immune cell infiltration between BC and bladder tissue was observed. Increased natural killer and CD8+ T cell infiltration was associated with longer OS, whereas a higher percentage of M0 macrophages among the total immune cells was associated with shorter OS. The number of M0 macrophages increased with increasing BC stage, whereas the percentage of activated memory CD4+ and CD8+ T cells decreased. Patients with BC were divided into three subgroups by hierarchical cluster analysis of immune cells, and each cluster was associated with distinct survival and immune characteristics. The data indicated differences in the cellular composition of TIICs in patients with BC. Moreover, these TIICs were shown to be potential drug targets and reliable prognostic indicators.

LINC01419 facilitates hepatocellular carcinoma growth and metastasis through targeting EZH2-regulated RECK.

Long non-coding RNAs (lncRNAs) have been reported to play significant roles in human tumorigenesis, for example, in hepatocellular carcinoma (HCC). This study explored the role of LINC01419, a new lncRNA, in HCC. In vitro study revealed that LINC01419 promotes growth and migration of HCC cells. Genes that affected cell proliferation and cell migration were identified using RNA-sequence. Subsequently, it was confirmed that LINC01419 binds to EZH2, leading to histone methylation of the RECK promoter. Interaction between LINC01419 and FUS stabilized EZH2 mRNA thereby enhancing EZH2 expression. Conclusively, the results of this study confirm that LINC01419 may serve as a potential target for HCC diagnosis and treatment.

MafF Is Regulated via the circ-ITCH/miR-224-5p Axis and Acts as a Tumor Suppressor in Hepatocellular Carcinoma.

MafF is a member of the basic leucine zipper (bZIP) transcription factor Maf family and is commonly downregulated in multiple cancers. But the expression and function of MafF in hepatocellular carcinoma (HCC) remain unclear. In this study, we investigated the relationship between endogenous MafF expression and HCC progression and explored the regulatory mechanism of MafF expression in HCC. We found that MafF decreased in HCC tissues and cells. Lentivirus-mediated MafF overexpression inhibited HCC cell proliferation and induced cell apoptosis. Bioinformatics analysis and luciferase assay identified MafF as a direct target of miR-224-5p. RNA pull-down assay demonstrated that circular RNA circ-ITCH could sponge miR-224-5p specifically in HCC. The rescue experiments further elucidated that the expression and antitumor effects of MafF could be regulated via the circ-ITCH/miR-224-5p axis. This study verified that MafF acted as a tumor suppressor in HCC and revealed the upstream regulation mechanism of MafF, which provided a new perspective for potential therapeutic targets of HCC.

Fatal outcome of atezolizumab in a patient with immune-mediated pneumonitis, thrombocytopenia, and cardiac dysfunction: A case report
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The anti-programmed cell death-ligand 1 (PD-L1) antibody atezolizumab is a promising agent for various cancers. Although immune-related adverse events (irAEs) induced by atezolizumab are rare, they can be severe. Clinical experience in irAE management is presently insufficient. Herein, we present a case of a patient with non-small cell lung cancer (NSCLC) who developed life-threatening irAEs including pneumonitis, thrombocytopenia, and cardiac dysfunction under immunotherapy with atezolizumab. Under expectant treatment and corticosteroid regimen, pneumonitis was totally resolved. However, thrombocytopenia and cardiac dysfunction did not improve. The patient sadly passed away 28 days after a single dose of atezolizumab. This case alarmed us once more to the importance of irAE management under cancer immunotherapy.
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circ_0001730 promotes proliferation and invasion via the miR-326/Wnt7B axis in glioma cells.

Aim: To study the role of circRNA (circ_0001730) in glioblastoma. Materials & methods: The interaction between circ_0001730 and miR-326 was confirmed by FISH, RNA pull down, RNA-binding protein immunoprecipitation and luciferase reporter assays. Cell proliferation and growth were determined by MTT, EdU and colony formation assays. Cell migration was assessed by the Boyden assay. Results: The levels of circ_0001730 were elevated in glioblastoma cell lines and tissues. circ_0001730 downregulation suppressed migration and proliferation in glioblastoma cells. SP1 bounds to the promoter of circ_0001730 host gene EPHB4 thereby increasing the expression of circ_0001730. circ_0001730 activated the Wnt/ß-catenin pathway via the miR-326/Wnt7B axis. Conclusion: circ_000173 promoted growth and invasion in glioblastoma cells via the miR-326/Wnt7B axis.

MicroRNA-224, negatively regulated by c-jun, inhibits growth and epithelial-to-mesenchymal transition phenotype via targeting ADAM17 in oral squamous cell carcinoma.

Abnormal expression of miR-224 has been reported to promote cancer progression. However, the role of miR-224 is seldom reported in oral squamous cell carcinoma (OSCC). We reported that miR-224 expression was significantly down-regulated in OSCC tissues and cell lines. Restoration of miR-224 decreased OSCC cell growth and invasion. In addition, luciferase and Western blot assays revealed that ADAM17 protein was a downstream target of miR-224. The overexpression of ADAM17 dismissed miR-224's effect on cell growth and invasion. We concluded that miR-224 inhibited OSCC cell growth and invasion through regulating ADAM17 expression. Subsequently, we revealed that c-jun directly bind to miR-224 promoter and decreased miR-224 expression. Taken together, these findings demonstrated that miR-224 may function as a tumour-suppressive microRNA in OSCC and suggested that miR-224 may be a potential therapeutic target for OSCC patients.

Silencing of microRNA-708 promotes cell growth and epithelial-to-mesenchymal transition by activating the SPHK2/AKT/ß-catenin pathway in glioma.

Aberrant microRNA-708 (miR-708) expression is frequently reported in cancer studies; however, its role in glioma has not been examined in detail. We investigated miR-708 function in glioma and revealed that miR-708 expression was significantly down-regulated in glioma tissues and cell lines. Restoration of miR-708 inhibited glioma cell growth and invasion both in vitro and in vivo. The oncogene SPHK2 (sphingosine kinase 2) was identified as a downstream target of miR-708 using luciferase and western blot assays. miR-708 inhibited AKT/ß-catenin signaling, which is activated by SPHK2. In addition, we revealed that miR-708 was transcriptionally repressed by EZH2 (enhancer of zeste homolog 2)-induced histone H3 lysine 27 trimethylation and promoter methylation. In summary, our findings revealed that miR-708 is a glioma tumor suppressor and suggest that miR-708 is a potential therapeutic target for glioma patients.

EVI1 promotes epithelial-to-mesenchymal transition, cancer stem cell features and chemo-/radioresistance in nasopharyngeal carcinoma.

BACKGROUND: Aberrant EVI1 expression is frequently reported in cancer studies; however, its role in nasopharyngeal carcinoma (NPC) has not been examined in detail. The aim of the present study is to investigate the involvement of EVI1 in progression and prognosis of NPC. METHODS: RT-PCR, immunohistochemistry and western blot assays were used to examine the expression of EVI1 in NPC tissues and cell lines. Fluorescence in situ hybridization assay was used to examine the amplification of EVI1 in NPC tissues. The biological effect of EVI1 was determined by both in vitro and in vivo studies. The dual-luciferase reporter assay was performed to confirm that EVI1 bind at E-cadherin andß-catenin promoters. The ChIP, EMSA, and coimmunoprecipitation combined with mass spectrometry assays were used to analyze the EVI1 regulated proteins. RESULTS: EVI1 expression level was up-regulated in NPC tissues and cell lines. EVI1 was amplificated in NPC tissues. We observed that EVI1 down-regulation decreased the cell proliferation and invasive capacity of NPC cells in vitro and in vivo. EVI1, snail, and HDAC1 formed a co-repressor complex to repress E-cadherin expression and ultimately contributed to epithelial mesenchymal transition (EMT) phenotype in NPC cells. In another way, EVI1 directly bound at ß-catenin promoter and activated its expression. ß-catenin mediated EVI1's function on cancer stem cells (CSCs) properties. EVI1 up-regulation predicted unfavorable prognosis and contributed to chemo/radio-resistance in NPC cells. Finally, we constructed arsenic trioxide-loaded nanoparticles (ALNPs) and revealed that ALNPs exerted anti-tumor effect in NPC cells. CONCLUSIONS: Our data indicated that EVI1 played an oncogenic role in NPC growth and metastasis and that EVI1 might serve as a novel molecular target for the treatment of NPC.

RASSF6-mediated inhibition of Mcl-1 through JNK activation improves the anti-tumor effects of sorafenib in renal cell carcinoma.

Ras association domain family member 6 (RASSF6) has been shown to act as a tumor suppressor and predictor of poor prognosis in renal cell carcinoma (RCC). However, little is known about the effects of RASSF6 on sorafenib resistance or the underlying mechanism. Here, we show that RASSF6 expression positively correlates with sorafenib sensitivity in RCC cells and human samples. Stable ectopic overexpression of RASSF6 in RCC cell lines reduces resistance to sorafenib in vitro and in vivo. At a molecular level, RASSF6 activates the JNK signaling pathway, which further contributes to Mcl-1 inhibition. Suppression of the JNK pathway can partially restore Mcl-1 expression and sorafenib resistance. Together, these findings suggest that RASSF6 inhibits sorafenib resistance by repressing Mcl-1 through the JNK-dependent pathway. RASSF6 may serve as a novel regulator for sorafenib therapy in RCC.

Down-regulation of microRNA-224 -inhibites growth and epithelial-to-mesenchymal transition phenotype -via modulating SUFU expression in bladder cancer cells.

Aberrant expression of miR-224 is usually found in cancer studies; however, the role of miR-224 has seldom been reported in bladder cancer (BC). We explored miR-224's function and the underlying mechanism in BC. It was found that miR-224 expression was significantly up-regulated in BC tissues and cell lines. Knockdown of miR-224 decreased BC cell growth and invasion both in vitro and in vivo. We identified the SUFU protein as a downstream target of miR-224 by using luciferase and western blot assays. We proposed that miR-224 promoted BC cell growth and invasion via sustaining the activity of Hedgehog pathway, which was negatively regulated by SUFU. Taken together, our study demonstrated that miR-224 may function as an onco-miR in BC and suggested that miR-224 may be a potential therapeutic target for BC patients.

Elevated Expression of Zinc Finger Protein 703 Promotes Cell Proliferation and Metastasis through PI3K/AKT/GSK-3ß Signalling in Oral Squamous Cell Carcinoma.

BACKGROUND/AIMS: Zinc finger protein 703 (ZNF703), initially identified as a novel oncogene in human breast cancer, is a member of the NET/NlZ family of zinc finger transcription factors. It is recognized that the overexpression of ZNF703 is associated with various types of human cancers, but the role and molecular mechanism of ZNF703 in oral squamous cell carcinoma (OSCC) are unknown. METHODS: ZNF703 expression levels were examined in OSCC tissues and non-cancerous tissues by qRT-PCR and immunohistochemistry (IHC). The molecular mechanisms of ZNF703 and its effects on cell growth and metastasis were explored in vitro and in vivo using the CCK8 assay, colony formation assay, cell cycle analysis, migration and invasion assays, wound-healing assay, western blotting and xenograft experiments in nude mice. RESULTS: In this study, ZNF703 was found to be upregulated in OSCC tissues compared to that in normal tissues at both mRNA and protein levels, and its expression level was closely correlated with the overall survival of patients with OSCC. Silencing of the ZNF703 gene in OSCC cells significantly inhibited cell growth and metastasis in vitro and in vivo. Conversely, the overexpression of ZNF703 in OSCC cells promoted cancer growth and metastasis in vitro. Mechanistically, ZNF703 activated the PI3K/AKT/GSK-3ß signalling pathway and its downstream effectors, thus regulating the cell cycle and epithelial-mesenchymal transition (EMT). Furthermore, the promotive effects of ZNF703 on cellular proliferation and metastasis could be rescued by LY294002 (a PI3K-specific inhibitor) and MK2206 (an Akt-specific inhibitor). CONCLUSION: The results show that ZNF703 promotes cell growth and metastasis through PI3K/Akt/GSK-3ß signalling in OSCC and that it may be a promising target in the treatment of patients with OSCC.

Methylation-mediated silencing of microRNA-211 promotes cell growth and epithelial to mesenchymal transition through activation of the AKT/ß-catenin pathway in GBM.

Aberrant expression of miR-211 has frequently been reported in cancer studies; however, its role in glioblastoma multiforme (GBM) has not been examined in detail. We investigated the function and the underlying mechanism of miR-211 in GBM. We revealed that miR-211 was downregulated in GBM tissues and cell lines. Restoration of miR-211 inhibited GBM cell growth and invasion both in vitro and in vivo. The epithelial to mesenchymal transition (EMT) phenotype was reversed when miR-211 expression was restored. HMGA2 was identified as a down-stream target of miR-211. MiR-211 had an inhibitory effect on AKT/ß-catenin signaling, which was reversed by HMGA2 overexpression or miR-211 restoration. In addition, miR-211 was transcriptionally repressed by EZH2-induced H3K27 trimethylation and promoter methylation. Overall, our findings revealed miR-211 as a tumor suppressor in GBM and mir-211 may be a potential therapeutic target for GBM patients.

miR-181a-5p, an inducer of Wnt-signaling, facilitates cell proliferation in acute lymphoblastic leukemia.

Uncontrolled Wnt signaling causes leukemia. Inactivation of Wnt antagonists could play an important role in leukemia progression by activating the Wnt/ß-catenin pathway. Wnt inhibitory factor-1 (WIF1) is one of the important Wnt antagonists. Few miRNAs have been reported to directly target this gene in hematopoiesis. Here, we observed that miR-181a-5p expression was markedly overexpressed in several leukemia cell lines and acute lymphoblastic leukemia (ALL) samples compared with that noted in normal peripheral blood mononuclear cells. MTT assays, soft agar colony formation assays and flow cytometry analysis collectively showed that ectopic expression of miR-181a-5p induced ALL cell growth and proliferation. Furthermore, a mechanistic study disclosed that miR-181a-5p directly downregulated WIF1 expression by binding to its 3'-UTR, and further activated Wnt/ß­catenin signaling. These findings provide a novel mechanistic insight into the role of miR-181a-5p in ALL cell growth and proliferation and implicate miR-181a-5p as an attractive candidate for ALL therapy.

Long non-coding RNA XIST promotes cell growth and invasion through regulating miR-497/MACC1 axis in gastric cancer.

Abnormal expression of long non-coding RNA (lncRNAs) often contributes to unrestricted growth and invasion of cancer cells. LncRNA XIST expression is up-regulated in several cancers, however, its modulatory mechanism in gastric cancer (GC) has not been elucidated. In the present study, we found that XIST expression was significantly increased in GC tissues and cell lines. LncRNA XIST promoted cell cycle progression from the G1 phase to the S phase and protected cells from apoptosis, which contributed to GC cell growth. LncRNA XIST also contributed to GC cell invasion both in vitro and in vivo. We revealed that XIST functioned as competing endogenous RNA to repress miR-497, which controlled its down-stream target MACC1. We proposed that XIST was responsible for GC cell proliferation and invasion and XIST exerted its function through the miR-497/MACC1 axis. Our findings suggested that lncRNA XIST may be a candidate prognostic biomarker and a target for new therapies in GC patients.

Celecoxib suppresses autophagy and enhances cytotoxicity of imatinib in imatinib-resistant chronic myeloid leukemia cells.

BACKGROUND: Chronic myelogenous leukemia (CML) is a hematological stem cell disorder. Tyrosine kinase inhibitors (TKIs) are the standard treatments for CML, but a number of patients fail to respond effectively due to gene mutations. Celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, has been shown to have anti-tumor effect on solid tumor whereas the anti-CML effect and its underlying mechanism have not been completely elucidated. METHODS: The cytotoxic effects of celecoxib and/or imatinib were evaluated by MTT assay. Cell cycle distribution was examined by propidium iodide (PI) assay. Apoptosis or necrosis was analyzed by Annexin-V/PI, Hoechst 33342 staining and Western blot assays. Autophagy suppression effect of celecoxib was examined by Western blot and LysoTracker probe labelling. Lysosensor probe labelling was used to detect the effect of celecoxib on the lysosomal function. RESULTS: In this study, we found that celecoxib had therapy efficacy in KBM5 and imatinib-resistant KBM5-T315I CML cell lines. Celecoxib caused significant cytotoxic effect in both cell lines, especially in KBM5-T315I cells exposed to celecoxib for 72 h. Moreover, celecoxib induced necrosis and apoptosis while inhibited autophagy in CML cell lines and patient samples. Furthermore, this study demonstrated that celecoxib prevented the autophagic flux by inhibiting lysosome function. Celecoxib was tested in combination with imatinib, demonstrating that celecoxib could strengthen the cytotoxicity of imatinib in imatinib-resistant CML cells. CONCLUSIONS: These findings showed that celecoxib had therapy efficacy on CML cells. And it is first time to demonstrate that celecoxib is an autophagy suppresser and a combination of celecoxib and imatinib might be a promising new therapeutic strategy for imatinib-resistant CML cells.

Upregulation of metastasis-associated gene 2 promotes cell proliferation and invasion in nasopharyngeal carcinoma.

AIMS: Metastasis-associated gene 2 (MTA2) is reported to play an important role in tumor progression, but little is known about the role of MTA2 in nasopharyngeal carcinoma (NPC). The aim of the study was to explore the expression and function of MTA2 in NPC. METHODS: Expression of MTA2 in NPC tissues and cell lines was detected by immunohistochemistry and Western blotting. Relationship between MTA2 expression and clinicopathological features was analyzed. Stable MTA2-overexpressing and MTA2-siliencing NPC cells were established by transfection with plasmids encoding MTA2 cDNA and lentivirus-mediated short hairpin RNA, respectively. Cell viability was determined by Cell Counting Kit-8 and colony formation assay. Cell migration ability was evaluated by wound healing and transwell invasion assay. The impact of MTA2 knockdown on growth and metastasis of CNE2 cells in vivo was determined by nude mouse xenograft models. Expression of several Akt pathway proteins was detected by Western blotting. RESULTS: MTA2 was upregulated in NPC tissues and three NPC cell lines detected (CNE1, CNE2, and HNE1). MTA2 expression was related to clinical stage and lymph node metastasis of patients with NPC. MTA2 upregulation promoted proliferation and invasion of CNE1 cells, while MTA2 depletion had opposite effects on CNE2 cells. Moreover, MTA2 depletion suppressed growth and metastasis of CNE2 cells in vivo. MTA2 overexpression activated Akt and upregulated the expression of matrix metalloproteinase 7 and cyclin D1. CONCLUSION: We conclude that MTA2 acts as an oncogene in tumorigenesis of NPC. MTA2 may be a potential target for gene therapy in NPC.

Inhibition of mesothelioma cancer stem-like cells with adenovirus-mediated NK4 gene therapy.

Malignant mesothelioma (MM) is a highly invasive and chemoresistant malignancy induced by asbestos fibers. NK4, a hepatocyte growth factor antagonist and angiogenesis inhibitor, consists of the N-terminal hairpin domain and four kringle domains of the α-chain of hepatocyte growth factor. The therapeutic potential of NK4 has been demonstrated in a variety of tumor types. However, the mechanisms by which NK4 inhibits tumor growth have not been well delineated. In this study, it is shown that the NK4 adenovirus (Ad-NK4) potently inhibits cell viability, invasiveness and tumorigenicity of human MM cells. Significantly, this study demonstrates for the first time that Ad-NK4 inhibits cancer stem-like cell (CSC) properties as assessed by spheroid formation assay, side population analysis and flow cytometric sorting of CD24 cells. In addition to inhibiting phosphorylation of Met and AKT, Ad-NK4 markedly suppressed the active form of ß-catenin, a key mediator of both Wnt and AKT pathways. It is further demonstrated that expression of NK4 suppresses ß-catenin nuclear localization and transcriptional activity. Intriguingly, the expression levels of Oct4 and Myc, two critical stem cell factors and downstream targets of ß-catenin, were also diminished by Ad-NK4. Furthermore, the strong antitumor effect of NK4 was found to be linked to its ability to inhibit CSCs as revealed by immunohistochemical examination of tumor specimens from a mouse xenograft model of human MM. These findings suggest that NK4 acts as a CSC inhibitor by impeding Met/AKT/ß-catenin signaling and holds promise for achieving durable therapeutic responses in MM by constraining the CSC component of these aggressive tumors.

MTA1 overexpression induces cisplatin resistance in nasopharyngeal carcinoma by promoting cancer stem cells properties.

Themetastasis-associated gene 1 (MTA1) oncogene hasbeen suggested to be involved in the regulation of cancer progression. However, there is still no direct evidence that MTA1 regulates cisplatin (CDDP) resistance, as well as cancer stem cell properties. In this study, we found that MTA1 was enriched in CNE1/CDDP cells. Knock down of MTA1 in CNE1/CDDP cells reversed CSCs properties and CDDP resistance. However, ectopic expression of MTA1 in CNE1 cells induced CSCs phenotypes and CDDP insensitivity. Interestingly, ectopic overexpression of MTA1-induced CSCs properties and CDDP resistance were reversed in CNE1 cells after inhibition of PI3K/Akt by LY294002. In addition, MTA1 expression and Akt activity in CNE1/CDDP cells was much higher than that in CNE1 cells. These results suggested that MTA1 may play a critical role in promoting CDDP resistance in NPC cells by regulatingcancer stem cell properties via thePI3K/Akt signaling pathway. Our findings suggested that MTA1 may be a potential target for overcoming CDDP resistance in NPC therapy.