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Background: Amplification of 3q26 is one of the most frequent genetic alterations in many human malignancies. Recently, we isolated a novel oncogene eIF-5A2 within the 3q26 region. Functional study has demonstrated the oncogenic role of eIF-5A2 in the initiation and progression of human cancers. In the present study, we aim to investigate the physiological and pathological effect of eIF-5A2 in an eIF-5A2 transgenic mouse model., Methods: An eIF-5A2 transgenic mouse model was generated using human eIF-5A2 cDNA. The eIF-5A2 transgenic mice were characterized by histological and immunohistochemistry analyses. The aging phenotypes were further characterized by wound healing, bone X-ray imaging and calcification analysis. Mouse embryo fibroblasts (MEF) were isolated to further investigate molecular mechanism of eIF-5A2 in aging., Results: Instead of resulting in spontaneous tumor formation, overexpression of eIF-5A2 accelerated the aging process in adult transgenic mice. This included decreased growth rate and body weight, shortened life span, kyphosis, osteoporosis, delay of wound healing and ossification. Investigation of the correlation between cellular senescence and aging showed that cellular senescence is not required for the aging phenotypes in eIF-5A2 mice. Interestingly, we found that activation of eIF-5A2 repressed p19 level and therefore destabilized p53 in transgenic mouse embryo fibroblast (MEF) cells. This subsequently allowed for the accumulation of chromosomal instability, such as errors in cell dividing during metaphase and anaphase. Additionally, a significantly increase in number of aneuploidy cells (p < 0.05) resulted from an increase in the incidences of misaligned and lagging chromosomal materials, anaphase bridges, and micronuclei in the transgenic mice., Conclusion: These observations suggest that eIF-5A2 mouse models could accelerate organismal aging by increasing chromosome instability.

Tumors usually display fetal‐like characteristics, and many oncofetal proteins have been identified. However, fetal‐like reprogramming of RNA splicing in hepatocellular carcinoma (HCC) is poorly understood. Here, it is demonstrated that the expression of epithelial splicing regulatory protein 2 (ESRP2), an RNA splicing factor, is suppressed in fetal hepatocytes and HCC, in parallel with tumor progression. By combining RNA‐Seq with splicing analysis, it is identified that ESRP2 controls the fetal‐to‐adult switch of multiple splice isoforms in HCC. Functionally, ESRP2 suppressed cell proliferation and migration by specifically switching the alternative splicing (AS) of the TAK1 gene and restraining the expression of the fetal and oncogenic isoform, TAK1_ΔE12. Notably, aberrant TAK1 splicing led to the activation of p38MAPK signaling and predicted poor prognosis in HCC patients. Further investigation revealed that TAK1_ΔE12 protein interacted closely with TAB3 and formed liquid condensation in HCC cells, resulting in p38MAPK activation, enhanced cell migration, and accelerated tumorigenesis. Loss of ESRP2 sensitized HCC cells to TAK1 kinase inhibitor (TAK1i), promoting pyroptotic cell death and CD8+ T cell infiltration. Combining TAK1i with immune checkpoint therapy achieved potent tumor regression in mice. Overall, the findings reveal a previously unexplored onco‐fetal reprogramming of RNA splicing and provide novel therapeutic avenues for HCC. [ABSTRACT FROM AUTHOR]

Background: Tumor‐associated immune factors are heterogeneous and play an important role in determining outcome in cancer patients. In this study, the expression levels of immune factors in tumor tissue‐conditioned media from lung squamous cell carcinoma (LUSC) and lung adenocarcinoma (LUAD) were analyzed. Methods: LUAD and LUSC tissue specimens were collected immediately after surgery for antibody array analysis and real‐time quantitative PCR. Results: Higher levels of chemokines MCP1/CCL2 (21.11‐fold increase) and MIP‐1β/CCL4 (19.33‐fold increase) were identified in LUAD than in LUSC. Western blot and quantitative real‐time PCR analyses showed higher co‐expression of CCL2 and CCL4 in LUAD tissues compared to LUSC (P < 0.0001). Immunofluorescent co‐staining showed a high percentage of CCL2+/CD68+ and CCL4+/CD68+ tumor‐associated macrophages in LUAD compared to LUSC tissues, which might be responsible for the higher expression of CCL2 and CCL4 in LUAD samples. Kaplan–Meier curves showed that CCL2 overexpression in patients with LUSC was associated with beneficial overall survival (OS; P = 0.048) and progression‐free survival (PFS; P = 0.012); however, LUAD patients with higher CCL2 expression had unfavorable OS (P = 6.7e−08) and PFS (P = 0.00098). Similarly, CCL4 overexpression predicted favorable PFS (P = 0.021) in patients with LUSC, but patients with high CCL4 levels in LUAD had shorter OS (P = 0.013). Conclusion: Our study revealed that CCL2 and CCL4 expression levels could serve as potential prognostic biomarkers and therapeutic targets for NSCLC patients. [ABSTRACT FROM AUTHOR]

Background: Deletion of 3p is one of the most frequent genetic alterations in esophageal squamous cell carcinoma (ESCC), suggesting the existence of one or more tumor suppressor genes (TSGs) within these regions. In this study, one TSG, CACNA2D3 at 3p21.1, was characterized. Methods: Expression of CACNA2D3 in ESCCs was tested by quantitative real-time PCR and tissue microarray. The mechanism of CACNA2D3 downregulation was investigated by methylation-specific polymerase chain reaction (MS-PCR). The tumor suppressive function of CACNA2D3 was characterized by both in vitro and in vivo tumorigenic assays, cell migration and invasion assays. Results: CACNA2D3 was frequently downregulated in ESCCs (24/48, 50%), which was significantly associated with promoter methylation and allele loss (P<0.05). Tissue microarray result showed that downregulation of CACNA2D3 was detected in (127/224, 56.7%) ESCCs, which was significantly associated with lymph node metastasis (P = 0.01), TNM staging (P = 0.003) and poor outcome of ESCC patients (P<0.05). Functional studies demonstrated that CACNA2D3 could inhibit tumorigenicity, cell motility and induce apoptosis. Mechanism study found that CACNA2D3 could arrest cell cycle at G1/S checkpoint by increasing expressions of p21 and p53 and decreasing expression of CDK2. In addition, CACNA2D3 could upregulate intracellular free cytosolic Ca2+ and subsequently induce apoptosis. Conclusion: CACNA2D3 is a novel TSG responsible to the 3p21 deletion event and plays a critical suppressing role in the development and progression of ESCC. [ABSTRACT FROM AUTHOR]

Pirh2 is a Ring-H2 domain containing E3 ubiquitin ligase that targets several important tumor suppressor genes for proteasomal degradation. Overexpression of Pirh2 is frequently detected in many clinical tumor tissues including hepatocellular carcinoma (HCC). However, the molecular mechanism of Pirh2 activation in tumorigenesis still remains poorly understood. In this study, we find a Pirh2-binding protein, SCYL1 binding protein 1 (SCYL1BP1), that can promote the ubiquitin-dependent degradation of Pirh2. SCYL1BP1 colocalized with Pirh2 in the cytoplasm and prevented its localization to the nucleus. Ectopic expression of SCYL1BP1 increased the expression of p53 and further inhibited the G1/S transition of HCC cell lines. Conversely, knock down of SCYL1BP1 restored the expression of Pirh2 and inhibited p53 at protein level. Functional assays found that reintroduction of SCYL1BP1 into HCC cell lines significantly inhibited cell proliferation, foci formation, colony formation in soft agar and tumor formation in nude mice, suggesting the strong tumor-suppressive function of SCYL1BP1 in HCC progression. Furthermore, SCYL1BP1 was found to be frequently downregulated in HCC clinical specimens compared to their paired non-tumor tissues by immunohistochemical staining. Taken together, our data suggested that the interaction of SCYL1BP1/Pirh2 could accelerate Pirh2 degradation through an ubiquitin-dependent pathway. SCYL1BP1 may function as an important tumor suppressor gene in HCC development.Abbreviations:CHXcycloheximideCo-IPco-immunoprecipitaionCULATRCommittee on the Use of Live Animals in Teaching and ResearchHA-UbHA-tagged ubiquitinHCChepatocellular carcinomaIgGimmunoglobulin GIHCimmunohistochemicalPLAGL2Pleomorphic Adenoma Gene Like 2qPCRquantitative real-time PCRRNAiRNA interferenceSCYL1BP1SCYL1 binding protein 1TIP60Tat-interactive protein of 60 kDaVec-LO2vector-transfected LO2XTT2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide. [ABSTRACT FROM AUTHOR]

Summary: YKL-40 is a growth factor for connective tissue cells and a migration factor for endothelial cells. Elevated serum level of YKL-40 has been associated with poor prognosis in many cancers. However, the status of YKL-40 expression and its clinical/prognostic significance in gastric cancer are unclear. In this study, the expression of YKL-40 was studied by immunohistochemistry in gastric cancer tissue microarray containing 172 primary gastric cancer cases and 70 adjacent nonneoplastic mucosa specimens. The correlations between YKL-40 expression and clinicopathologic features, as well as activation of PI3K/Akt pathways were addressed. Expression of YKL-40 was significantly higher in gastric cancer tissues than that in adjacent nonneoplastic tissues. Overexpression YKL-40 was found in 28.4% of gastric cancers and was significantly associated with tumor invasion (P = .007) and lymph node metastasis (P = .009). For survival study, overexpression of YKL-40 was significantly associated with worse outcome (P = .001). When known clinical variables were added to a multivariate analysis, TNM stage, tumor size, and overexpression of YKL-40 emerged as independent prognostic factors. Further study indicated that the oncogenic function of YKL-40 might be through the activation of Akt pathway. These results suggest that overexpression of YKL-40 is correlated with the aggressive behavior of tumor cells, which could be used as an independent molecular marker for the predicting poor prognosis of patients with gastric cancer. [Copyright &y& Elsevier]

Objective: Hepatocellular carcinoma (HCC) is a heterogeneous tumour displaying a complex variety of genetic and epigenetic changes. In human cancers, aberrant post-transcriptional modifications, such as alternative splicing and RNA editing, may lead to tumour specific transcriptome diversity. Design: By utilising large scale transcriptome sequencing of three paired HCC clinical specimens and their adjacent non-tumour (NT) tissue counterparts at depth, we discovered an average of 20 007 inferred A to I (adenosine to inosine) RNA editing events in transcripts. The roles of the double stranded RNA specific ADAR (Adenosine DeAminase that act on RNA) family members (ADARs) and the altered gene specific editing patterns were investigated in clinical specimens, cell models and mice. Results: HCC displays a severely disrupted A to I RNA editing balance. ADAR1 and ADAR2 manipulate the A to I imbalance of HCC via their differential expression in HCC compared with NT liver tissues. Patients with ADAR1 overexpression and ADAR2 downregulation in tumours demonstrated an increased risk of liver cirrhosis and postoperative recurrence and had poor prognoses. Due to the differentially expressed ADAR1 and ADAR2 in tumours, the altered gene specific editing activities, which was reflected by the hyper-editing of FLNB (filamin B, β) and the hypo-editing of COPA (coatomer protein complex, subunit α), are closely associated with HCC pathogenesis. In vitro and in vivo functional assays prove that ADAR1 functions as an oncogene while ADAR2 has tumour suppressive ability in HCC. Conclusions: These findings highlight the fact that the differentially expressed ADARs in tumours, which are responsible for an A to I editing imbalance, has great prognostic value and diagnostic potential for HCC.

Background & Aims: Esophageal squamous cell carcinoma (ESCC) is the most commonly observed histologic subtype of esophageal cancer. ESCC is believed to develop via accumulation of numerous genetic alterations, including inactivation of tumor suppressor genes and activation of oncogenes. We searched for transcripts that were altered in human ESCC samples compared with nontumor tissues. Methods: We performed integrative transcriptome sequencing (RNA-Seq) analysis using ESCC samples from 3 patients and adjacent nontumor tissues to identify transcripts that were altered in ESCC tissue. We performed molecular and functional studies of the transcripts identified and investigated the mechanisms of alteration. Results: We identified protein tyrosine kinase 6 (PTK6) as a transcript that was significantly down-regulated in ESCC tissues and cell lines compared with nontumor tissues or immortalized normal esophageal cell lines. The promoter of the PTK6 gene was inactivated in ESCC tissues at least in part via hypermethylation and histone deacetylation. Knockdown of PTK6 in KYSE30 ESCC cells using small hairpin RNAs increased their ability to form foci, migrate, and invade extracellular matrix in culture and form tumors in nude mice. Overexpression of PTK6 in these cells reduced their proliferation in culture and tumor formation in mice. PTK6 reduced phosphorylation of Akt and glycogen synthase kinase (GSK)3β, leading to activation of β-catenin. Conclusions: PTK6 was identified as a transcript that is down-regulated in human ESCC tissues via epigenetic modification at the PTK6 locus. Its product appears to regulate cell proliferation by reducing phosphorylation of Akt and GSK3β, leading to activation of β-catenin. Reduced levels of PTK6 promote growth of xenograft tumors in mice; it might be developed as a marker of ESCC. [ABSTRACT FROM AUTHOR]

Abstract: Non-small cell lung cancer (NSCLC) accounts for approximately 70% of all lung cancer-related deaths worldwide. Prognostic markers are essential for the early detection of lung cancer in patients. In this study, we first identified microRNA146 (miR-146) expression in cancer cell lines using miRNA in situ hybridization (MISH) and confirmed the accuracy of MISH using q-RT-PCR. In addition, two different systems, BCIP/NBT and ELF, were used to detect the signal for a comparative analysis of the specificity of MISH. Compared to the BCIP/NBT system, the ELF detection system was more effective for MISH. Furthermore we detected the expression of miR-146 in NSCLC tissues (43 cases) and normal tissues (32 cases). Based on our results, we can conclude that miR-146 is more highly expressed in cancer tissue than normal tissue (t-test, P<0.05) and that miR-146 can predict the prognosis of NSCLC by MISH. Our findings preliminary demonstrate that MISH can be applied as a molecular diagnostic tool to determine the expression and localization of miRNAs in cancer tissues and that miR-146, determined by MISH, predicts the prognosis of NSCLC patients. [Copyright &y& Elsevier]

Highlights: [•] Overexpression of CENPF is frequently detected in HCC. [•] Upregulation of CENPF serves as an independent prognosis factor in HCC patients. [•] CENPF functions as an oncogene in HCC by promoting cell G2/M transition. [ABSTRACT FROM AUTHOR]

Background/Aims: We previously demonstrated that two linked single nucleotide polymorphisms (SNPs) at −408 and −3 of type I interferon receptor 1 (IFNAR1) promoter are associated with susceptibility to chronic HBV infection. We aimed to elucidate the mechanism by which −3 and/or −408 C/T SNPs had such profound effects. Methods: A functional SNP in IFNAR1 promoter was defined by reporter gene assay, mutational analysis, flow cytometry analysis and gel shift assay. The nuclear protein binding to the essential polymorphic site was identified and its effect on transcriptional regulation of IFNAR1 was further demonstrated in a series of ex vivo and in vivo experiments. Results: We found C>T change at the −3 locus reduced the transcriptional activity of IFNAR1 promoter. High mobility group B protein 1 (HMGB1) and PARP-1 were co-recruited to the IFNAR1 promoter to regulate its transcription. We demonstrated HMGB1-binding affinity to IFNAR1 promoter was reduced in the −3T variant. Additionally, PARP-1, a cofactor for IFNAR1 transcription activation, was significantly suppressed by HBV. Conclusion: Upon HBV infection, decreased binding affinity of HMGB1 to the IFNAR1 promoter −3T variant is aggravated by the suppressed PARP-1 expression caused by HBV, resulting in a further attenuated IFNAR1 expression. This compromises the antiviral and immuno-regulatory effects of IFN-α/β, which may in turn affect the clinical outcome of HBV infection. [Copyright &y& Elsevier]