BST2 promotes gastric cancer metastasis under the regulation of HOXD9 and PABPC1.

Gastric cancer (GC) constitutes substantial cancer mortality worldwide. Several cancer types aberrantly express bone marrow stromal cell antigen 2 (BST2), yet its functional and underlying mechanisms in GC progression remain unknown. In our study, RNA sequencing data revealed that BST2 was transcriptionally activated by homeobox D9 (HOXD9). BST2 was significantly upregulated in GC tissues and promoted epithelial-mesenchymal transition and metastasis of GC. BST2 knockdown reversed HOXD9's oncogenic effect on GC metastasis. Moreover, BST2 messenger RNA stability could be enhanced by poly(A) binding protein cytoplasmic 1 (PABPC1) through the interaction between BST2 3'-UTR and PABPC1 in GC cells. PABPC1 promoted GC metastasis, which BST2 silencing attenuated in vitro and in vivo. In addition, positive correlations among HOXD9, BST2, and PABPC1 were established in clinical samples. Taken together, increased expression of BST2 induced by HOXD9 synergizing with PABPC1 promoted GC cell migration and invasion capacity.

Preparation and epitope mapping of monoclonal antibodies against African swine fever virus p22 protein.

African swine fever (ASF), caused by the African swine fever virus (ASFV), is now widespread in many countries and severely affects the commercial rearing of swine. Rapid and early diagnosis is crucial for the prevention of ASF. ASFV mature virions comprise the inner envelope protein, p22, making it an excellent candidate for the serological diagnosis and surveillance of ASF. In this study, the prokaryotic-expressed p22 recombinant protein was prepared and purified for immunization in mice. Four monoclonal antibodies (mAbs) were identified using hybridoma cell fusion, clone purification, and immunological assays. The epitopes of mAbs 14G1 and 22D8 were further defined by alanine-scanning mutagenesis. Our results showed that amino acids C39, K40, V41, D42, C45, G48, E49, and C51 directly bound to 14G1, while the key amino acid epitope for 22D8 included K161, Y162, G163, D165, H166, I167, and I168. Homologous and structural analysis revealed that these sites were highly conserved across Asian and European ASFV strains, and the amino acids identified were located on the surface of p22. Thus, our study contributes to a better understanding of the antigenicity of the ASFV p22 protein, and the results could facilitate the prevention and control of ASF.

The ATF2/miR-3913-5p/CREB5 axis is involved in the cell proliferation and metastasis of colorectal cancer.

Various miRNAs have been shown to participate in the tumor progression and development of colorectal cancer (CRC). However, the role of miR-3913-5p in CRC are yet to be clearly defined. In the present study, we determine that miR-3913-5p is downregulated in CRC cell lines and CRC tissues. Exogenous miR-3913-5p expression weakens the CRC cells growth, migration and invasion. Mechanistically, miR-3913-5p directly targets the 3'UTR of CREB5. Overexpression of CREB5 reverses the suppression of CRC cells proliferation, migration and invasion induced by miR-3913-5p. Furthermore, ATF2 negatively regulates the transcription of miR-3913-5p by binding to its promoter. CREB5 can cooperate with ATF2. CREB5 is required for ATF2 in regulating miR-3913-5p. Finally, inverse correlations can be found between the expressions of miR-3913-5p and CREB5 or ATF2 in CRC tissues. Thus, a plausible mechanism of ATF2/miR-3913-5p/CREB5 axis regulating CRC progression is elucidated. Our findings suggest that miR-3913-5p functions as a tumor suppressor in CRC. ATF2/miR-3913-5p/CREB5 axis might be a potential therapeutic target against CRC progression.

The HOXD9-mediated PAXIP1-AS1 regulates gastric cancer progression through PABPC1/PAK1 modulation.

Long non-coding RNAs (lncRNAs) have been functionally characterised in various diseases. LncRNA PAX-interacting protein 1-antisense RNA 1 (PAXIP1-AS1) has reportedly been associated with cancer development. However, its role in gastric cancer (GC) remains poorly understood. Here, we showed that PAXIP1-AS1 was transcriptionally repressed by homeobox D9 (HOXD9) and was significantly downregulated in GC tissues and cells. Decreased expression of PAXIP1-AS1 was positively correlated with tumour progression, while PAXIP1-AS1 overexpression inhibited cell growth and metastasis both in vitro and in vivo. PAXIP1-AS1 overexpression significantly attenuated HOXD9-enhanced epithelial-to-mesenchymal transition (EMT), invasion and metastasis in GC cells. Poly(A)-binding protein cytoplasmic 1 (PABPC1), an RNA-binding protein, was found to enhance the stability of PAK1 mRNA, leading to EMT progress and GC metastasis. PAXIP1-AS1 was found to directly bind to and destabilise PABPC1, thereby regulating EMT and metastasis of GC cells. In summary, PAXIP1-AS1 suppressed metastasis, and the HOXD9/PAXIP1-AS1/PABPC1/PAK1 signalling axis may be involved in the progression of GC.

The LINC00501-HSP90B1-STAT3 positive feedback loop promotes malignant behavior in gastric cancer cells.

Long non-coding RNAs (lncRNAs) have been implicated in gastric cancer (GC) carcinogenesis and progression. However, the role of LINC00501 in GC growth and metastasis remains unclear. In this study, we found that LINC00501 was frequently upregulated in GC cells and tissues and was closely related to adverse GC clinicopathological features. Aberrant overexpression of LINC00501 promoted GC cell proliferation, invasion, and metastasis both in vitro and in vivo. Mechanistically, LINC00501 stabilized client protein STAT3 from deubiquitylation by directly interacting with cancer chaperone protein HSP90B1. Furthermore, the LINC00501-STAT3 axis modulated GC cell proliferation and metastasis. In turn, STAT3 bound directly to the LINC00501 promoter and positively activated LINC00501 expression, thus forming a positive feedback loop, thereby accelerating tumor growth, invasiveness, and metastasis. In addition, LINC00501 expression was positively correlated with STAT3 and p-STAT3 protein expression levels in gastric clinical samples. Our results reveal that LINC00501 acts as an oncogenic lncRNA and that the LINC00501-HSP90B1-STAT3 positive feedback loop contributes to GC development and progression, suggesting that LINC00501 may be a novel potential biomarker and treatment target for GC.

Evaluation of a novel disposable esophagogastroduodenoscopy system in emergency, bedside, and intraoperative settings: Pilot study (with videos).

OBJECTIVES: The disposable esophagogastroduodenoscopy (EGD) system is a novel endoscopic device which is highly portable and is designed to eliminate the risk of cross-infection caused by reusable EGD. This study aimed to investigate the feasibility and safety of disposable EGD in emergency, bedside, and intraoperative settings. METHODS: This was a prospective, single-center, noncomparative study. Disposable EGD was used for emergency, bedside, and intraoperative endoscopies in 30 patients. The primary end-point was the technical success rate of the disposable EGD. Secondary end-points included technical performance indicators including clinical operability, image quality score, procedure time, the incidence of device malfunction and/or failure, and the incidence of adverse events. RESULTS: A total of 30 patients underwent diagnosis and/or treatment with disposable EGD. Therapeutic EGD was performed on 13/30 patients, including hemostasis (n = 3), foreign body retrieval (n = 6), nasoenteric tube placement (n = 3), and percutaneous endoscopic gastrostomy (n = 1). The technical success rate was 100%: all procedures and indicated interventions were completed without changing to a conventional upper endoscope. The mean image quality score obtained immediately after procedure completion was 3.72 ± 0.56. The mean (± SD) procedure time was 7.4 (± 7.6) min. There were no device malfunctions or failures, device-related adverse events, or overall adverse events. CONCLUSION: The disposable EGD may be a feasible alternative to the traditional EGD in emergency, bedside, and intraoperative settings. Preliminary data show that it is a safe and effective tool for diagnosis and treatment in emergency and bedside upper gastrointestinal cases. TRIAL REGISTRATION: Chinese Clinical Trial Registry (Trial ID: ChiCTR2100051452, https://www.chictr.org.cn/showprojen.aspx?proj=134284).

Identification and Validation of a Novel Prognostic Gene Model for Colorectal Cancer.

Aims: Colon cancer (CRC), with high morbidity and mortality, is a common and highly malignant cancer, which always has a bad prognosis. So it is urgent to employ a reasonable manner to assess the prognosis of patients. We developed and validated a gene model for predicting CRC risk. Methods: The Gene Expression Omnibus (GEO) database was used to extract the gene expression profiles of CRC patients (N = 181) from GEO to identify genes that were differentially expressed between CRC patients and controls and then stable signature genes by firstly using both robust likelihood-based modeling with 1000 iterations and random survival forest variable hunting algorithms. Cluster analysis using the longest distance method was drawn out, and Kaplan-Meier (KM) survival analysis was used to compare the clusters. Meanwhile, the risk score was evaluated in three independent datasets including the GEO and Illumina HiSeq sequencing platforms. The corresponding risk index was calculated, and samples were clustered into high- and low-risk groups according to the median. And survival ROC analysis was used to evaluate the prognostic model. Finally, the Gene Set Enrichment Analysis (GSEA) was performed for further functional enrichment analyses. Results: A 10-gene model was obtained, including 7 negative impact factors (SLC39A14, AACS, ERP29, LAMP3, TMEM106C, TMED2, and SLC25A3) and 3 positive ones (CNPY2, GRB10, and PBK), which related with several important oncogenic pathways (KRAS signaling, TNF-α signaling pathway, and WNT signaling pathway) and several cancer-related cellular processes (epithelial mesenchymal transition and cellular apoptosis). By using colon cancer datasets from The Cancer Genome Atlas (TCGA), the model was validated in KM survival analysis (P ≤ 0.001) and significant analysis with recurrence time (P = 0.0018). Conclusions: This study firstly developed a stable and effective 10-gene model by using novel combined methods, and CRC patients might be able to use it as a prognostic marker for predicting their survival and monitoring their long-term treatment.

Disruption of the CCDC43-FHL1 interaction triggers apoptosis in gastric cancer cells.

The coiled-coil domain-containing protein 43 (CCDC43) is essential to promote gastric cancer (GC) proliferation and invasion, while four and a half LIM domains 1 (FHL1) involves GC cells apoptosis. We attempted to address inter-relationship between CCDC43 and FHL1 in modulating GC cells growth and apoptosis. Levels of protein expression were assessed by western blot, immunofluorescence. Using EdU, plate colony formation, Matrigel invasion and animal models, we evaluated the function in vitro and in vivo. Apoptosis was evaluated by flow cytometry and Hoechst 33258 staining. Reciprocal co-immunoprecipitation (co-IP) analyses indicated that CCDC43 physically interacted with FHL1. The expression of CCDC43 was negatively correlated with FHL1. Moreover, up-regulation of CCDC43 resulted in FHL1 level decline, and the reverse is also true. CCDC43 expressed jointly with FHL1 group significantly decreases the ability of the growth, metastasis and invasion of GC cells compared with that of the CCDC43 group. Furthermore, siRNA-mediated repression of CCDC43 results in dissociation from FHL1 and causes suppression of GC cell proliferation and metastasis. CCDC43 repression mediates the stability of FHL1 protein. In addition, CCDC43 interacts with FHL1. Knockdown of CCDC43 plus FHL1 overexpression inhibits proliferation and migration and induces apoptosis of GC cells in vitro and vivo.

USP3 promotes gastric cancer progression and metastasis by deubiquitination-dependent COL9A3/COL6A5 stabilisation.

As an important regulator of intracellular protein degradation, the mechanism of the deubiquitinating enzyme family in tumour metastasis has received increasing attention. Our previous study revealed that USP3 promotes tumour progression and is highly expressed in gastric cancer (GC). Herein, we report two critical targets, COL9A3 and COL6A5, downstream of USP3, via the isobaric tags for relative and absolute quantification technique. Mechanistically, we observed that USP3 interacted with and stabilised COL9A3 and COL6A5 via deubiquitination in GC. Importantly, we found that COL9A3 and COL6A5 were essential mediators of USP3-modulated oncogenic activity in vitro and in vivo. Examination of clinical samples confirmed that elevated expression of USP3, concomitant with increased COL9A3 and COL6A5 abundance, correlates with human GC progression. These data suggest that USP3 promotes GC progression and metastasis by deubiquitinating COL9A3 and COL6A5. These findings identify a mechanism of GC metastasis regarding USP3-mediated deubiquitinating enzyme activity and suggest potential therapeutic targets for GC management.

Vorinostat triggers miR-769-5p/3p-mediated suppression of proliferation and induces apoptosis via the STAT3-IGF1R-HDAC3 complex in human gastric cancer.

Previous reports have shown that histone deacetylase inhibitors (HDACi) can alter miRNA expression in a range of cancers. Both the 5p-arm and 3p-arm of mature miRNAs can be expressed from the same precursor and involved in cancer progress. Nevertheless, the detailed mechanism by which vorinostat (SAHA), a HDACi, triggers miR-769-5p/miR-769-3p-mediated suppression of proliferation and induces apoptosis in gastric cancer (GC) cells remains elusive. Here, we showed that the miRNA-seq analysis of GC cells treated with SAHA identified seven differentially expressed miRNAs with both strands of the miRNA duplex. miR-769-5p/miR-769-3p expression was downregulated in GC tissues compared with normal tissues. Functionally, high expression of miR-769-5p/miR-769-3p blocked the malignant abilities of GC cells. Mechanistically, miR-769-5p/miR-769-3p targeted IGF1R and IGF1R overexpression rescued the effects of miR-769-5p/miR-769-3p on GC cells growth and metastasis. Moreover, STAT3 bound to the promoter of miR-769. Furthermore, miR-769-5p/miR-769-3p expression was negatively regulated by the STAT3-IGF1R-HDAC3 complex. Besides, miR-769-5p/miR-769-3p synergized with SAHA to promote GC cells apoptosis. Our studies suggest that miR-769-5p/miR-769-3p acts as a tumor suppressor by the STAT3-IGF1R-HDAC3 complex. Moreover, SAHA triggers miR-769-5p/miR-769-3p-mediated inhibition of proliferation and induces apoptosis in GC cells.

Coexpression of HOXA6 and PBX2 promotes metastasis in gastric cancer.

HOXA6 gene plays a role of the oncogene in various cancers. Nonetheless, its effect on gastric cancer (GC) occurrence and development is still unclear. We analysed whether HOXA6 interacts with the PBX2 protein using the STRING database. The molecular mechanism by which HOXA6 synergizes with PBX2 in GC metastasis is not fully understood. Here, we found that the expression of HOXA6 was increased in GC tissues and cell lines. The upregulation of HOXA6 was closely associated with differentiation, lymph node metastasis, AJCC stage, TNM stage, and poor survival outcome in GC patients based on tissue microarray (TMA) data. Moreover, the overexpression of HOXA6 promoted, whereas siRNA-mediated repression of HOXA6 inhibited, the cell proliferation, migration, and invasion of GC cells. Furthermore, HOXA6 could physically interact with and stabilize PBX2. In addition, HOXA6 and PBX2 expression was positively correlated in GC cells and tissue. HOXA6 and PBX2 suppression in GC cells also led to decreased migration and invasion potential in vitro. In vivo, HOXA6 was shown to cooperate with PBX2 to enhance cell metastasis via orthotopic implantation. These data indicate that HOXA6 promotes cell proliferation, migration, and invasion and that the HOXA6-PBX2 axis may be a useful biomarker for disease progression in GC.

The POU2F1/miR-4490/USP22 axis regulates cell proliferation and metastasis in gastric cancer.

PURPOSE: Growing evidence indicates that aberrant expression of microRNAs contributes to tumor development. However, the biological role of microRNA-4490 (miR-4490) in gastric cancer (GC) remains to be clarified. METHODS: To explore the function of miR-4490 in GC, we performed colony formation, EdU incorporation, qRT-PCR, Western blotting, in situ hybridization (ISH), immunohistochemistry (IHC), flow cytometry, ChIP and dual-luciferase reporter assays. In addition, the growth, migration and invasion capacities of GC cells were evaluated. RESULTS: We found that miR-4490 was significantly downregulated in primary GC samples and in GC-derived cell lines compared with normal controls, and that this expression level was negatively correlated with GC malignancy. Exogenous miR-4490 expression not only reduced cell cycle progression and proliferation, but also significantly inhibited GC cell migration, invasion and epithelial-mesenchymal transition (EMT) in vitro. Mechanistically, we found that miR-4490 directly targets USP22, which mediates inhibition of GC cell proliferation and EMT-induced metastasis in vitro and in vivo. Moreover, we found through luciferase and ChIP assays that transcription factor POU2F1 can directly bind to POU2F1 binding sites within the miR-4490 and USP22 promoters and, by doing so, modulate their transcription. Spearman's correlation analysis revealed a positive correlation between USP22 and POU2F1 expression and negative correlations between miR-4490 and USP22 as well as miR-4490 and POU2F1 expression in primary GC tissues. CONCLUSION: Based on our results we conclude that miR-4490 acts as a tumor suppressor, and that the POU2F1/miR-4490/USP22 axis plays an important role in the regulation of growth, invasion and EMT of GC cells.

MicroRNA­500a­5p inhibits colorectal cancer cell invasion and epithelial­mesenchymal transition.

The development of malignant tumors is a series of complex processes, the majority of which have not been elucidated. The aim of the present study was to investigate the microRNAs (miRNAs/miR) that affect the migration and invasion abilities of CRC cells. Our previous reports have revealed that miR­500a­5p suppressed CRC cell growth and malignant transformation. The present study demonstrated that overexpression of miR­500a­5p reduced the expression of vimentin, while increasing the expression of E­cadherin. Inhibition of miR­500a­5p resulted in spindle­like morphological changes and reorganization of F­actin in CRC cells. Furthermore, miR­500a­5p attenuated the transforming growth factor­ß signaling pathway in EMT. Additionally, emodin inhibited the miR­500a­5p inhibitor and suppressed the EMT process. In animal models of metastasis using nude mice, EMT and LoVo cell metastasis was modulated by miR­500a­5p. Therefore, the findings of the present study demonstrated that miR­500a­5p is associated with a positive therapeutic outcome in terms of invasion/migration of CRC cells and mesenchymal­like cell changes.

HOXD9 promote epithelial-mesenchymal transition and metastasis in colorectal carcinoma.

BACKGROUND: HOXD9, a Hox family member, is involved in cancer growth and metastasis. But, its regulation mechanism at the molecular level particularly in colorectal cancer (CRC), is mostly unknown. METHODS: The HOXD9 protein expression levels were analyzed using immunofluorescence, immunohistochemistry (IHC) assays, and western blot. The in vivo and in vitro roles of HOXD9 in CRC were determined using colony formation and EdU incorporation, CCK-8, wound scratch and transwell invasion assay, and animal models. RESULTS: Expression of HOXD9 was higher in CRC than in matched healthy tissues. High expression of HOXD9 has significantly associated with the American Joint Committee on Cancer (AJCC) stages, tumor differentiation, lymph node metastasis, and other serious invasions, and it had a poor prognosis. In vitro, HOXD9 encouraged proliferation, movement and EMT processes in cells of CRC. Also, TGF-ß1 promoted the expression of HOXD9 and this effect was dependent on the dose and downregulation of HOXD9 repressed TGF-ß1 -induced EMT. In vivo, HOXD9 promoted the invasive and metastasis of CRC cells via orthotopic implantation. CONCLUSIONS: The ectopic expression of HOXD9 promoted the invasion metastasis in cells of the colorectal tumor by induction of EMT in vitro and vivo.

The CCDC43-ADRM1 axis regulated by YY1, promotes proliferation and metastasis of gastric cancer.

Previous studies have shown an association between coiled-coil domain-containing (CCDC) genes and different cancers. Our previous studies revealed that CCDC43 is highly expressed in colorectal cancer, but the expression and molecular mechanisms of CCDC43 in gastric cancer (GC) are yet to be determined. Here, we show that CCDC43 is overexpressed in gastric tissues. CCDC43 expression is closely related to tumor differentiation, lymph-node-metastasis, and prognosis of gastric cancer. Overexpression of CCDC43 promotes the proliferation, invasion, and metastasis of GC cells. CCDC43 may upregulate and stabilize ADRM1, resulting in the construction of the ubiquitin-mediated proteasome. In contrast, inhibition of ADRM1 could reverse the function of CCDC43 in GC both in vitro and in vivo. Our data demonstrate that transcription factor YY1 directly binds to CCDC43 and ADRM1 gene promoters, leading to over-expression of CCDC43 and ADRM1. Furthermore, in vitro experiments demonstrate that knock down of CCDC43 or ADRM1 attenuates the YY1-mediated malignant phenotypes. Finally, the association among YY1, CCDC43 and ADRM1 is validated in clinical samples. Our findings suggest that the CCDC43-ADRM1 axis regulated by YY1, promotes proliferation and metastasis of GC, and the axis may be a potential therapeutic target for GC.

Standing-type magnetically guided capsule endoscopy versus gastroscopy for gastric examination: multicenter blinded comparative trial.

AIM: To compare feasibility and safety after gastrointestinal checkup by standing-type magnetically controlled capsule endoscopy (SMCE) and conventional gastroscopy. METHODS: This was a prospective multicenter, blinded study that compared SMCE with gastroscopy in patients from April 2018 to July 2018. All patients first underwent SMCE and then subsequently had gastroscopy with i.v. anesthesia. We calculated the compliance rates of gastric lesion detection by SMCE using gastroscopy as the standard. Capsule retention rate, incidence of adverse events, and patient satisfaction were documented throughout the study. RESULTS: One hundred and sixty-one patients who completed SMCE and gastroscopy were included in the analysis. Positive compliance rate among SMCE and gastroscopy was 92.0% (95% CI: 80.77%-97.78%). Negative compliance rate was 95.5% (89.80%, 98.52%). Moreover, overall compliance rate was 94.41% (89.65%, 97.41%). Sixty-four pathological outcomes were identified. Of these 64 outcomes, 50 were detected by both procedures. The gastroscopy method neglected seven findings (such as five erosions, one polyp, and one ulcer). Furthermore, SMCE also overlooked seven lesions (i.e. one erosion, two polyps, one atrophy, and three submucosal tumors). Capsule retention or related adverse events were not reported. CONCLUSION: Standing-type magnetically controlled capsule endoscopy provides equivalent agreement with gastroscopy and may be useful for screening of gastric illnesses without any anesthesia.