Domperidone inhibits cell proliferation via targeting MEK and CDK4 in esophageal squamous cell carcinoma

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is one of the leading causes of digestive system tumor related death in the world. Unfortunately, effective chemopreventive agent is lack for patients with ESCC in clinical practice, which leads to the extremely high mortality rate.

METHODS

A library of prescribed drugs was screened for finding critical anti-tumor properties in ESCC cells. The phosphoproteomics, kinase array, pulldown assay and drug affinity responsive target stabilization assay (DARTS) were applied to explore mechanisms and searched for synergistic targets. Established models of PDX in mice were used to determine the therapeutic effect of domperidone.

RESULTS

After screening a library of prescribed drugs, we discovered that domperidone has anti-tumor properties. Domperidone, acting as a gastroprokinetic agent, has been widely used in clinic for gastrointestinal motility disorders. Despite limited research, there are indications that domperidone may have anti-tumor properties. In this study, we determined that domperidone significantly inhibited ESCC proliferation in vitro and in vivo. We employed phosphoproteomics to reveal p-ERK, and p-SMAD3 down-regulation upon domperidone treatment. Then, the results of kinase assay and pulldown assay further validated that domperidone directly combined with MEK1/2 and CDK4, leading to the inhibition of their kinase activity. Furthermore, our results revealed that MEK/ERK and CDK4/SMAD3 signal pathway were major pathways in domperidone against ESCC.

CONCLUSION

Collectively, these findings suggest that domperidone serves as an effective "multi-target" inhibitor of MEK1/2 and CDK4, offering potential benefits for the chemoprevention of ESCC.

Dihydroartemisinin inhibits the development of colorectal cancer by GSK-3β/TCF7/MMP9 pathway and synergies with capecitabine

Patients with colorectal cancer (CRC) suffer from poor prognosis and lack effective drugs. Dihydroartemisinin (DHA) has anti-cancer potential but the mechanism remains unclear. We elucidated the effects and mechanism of DHA on CRC development with the aim of providing an effective, low-toxicity drug and a novel strategy for CRC. Herein, proliferation assay, transwell assay, tube formation assay, metastasis models, PDX model and AOM/DSS model were used to reveal the effects of DHA on CRC. The key pathway and target were identified by RNA-seq, ChIP, molecular docking, pull down and dual-luciferase reporter assays. As a result, DHA showed a strong inhibitory effect on the growth, metastasis and angiogenesis of CRC with no obvious toxicity, and the inhibitory effect was similar to that of the clinical drug Capecitabine (Cap). Indeed, DHA directly targeted GSK-3β to inhibit CRC development through the GSK-3β/TCF7/MMP9 pathway. Meaningfully, DHA in combination with Cap enhanced the anti-cancer effect, and alleviated Cap-induced diarrhoea, immunosuppression and inflammation. In conclusion, DHA has the potential to be an effective and low-toxicity drug for the treatment of CRC. Furthermore, DHA in combination with Cap could be a novel therapeutic strategy for CRC with improved efficacy and reduced side effects.

Structural stability design of an optical mirror mount adjustment mechanism

The stability of beam pointing in a laser system depends on the consistency of the optical mirror mount. Typically, a locking mechanism is used to secure the adjustment mechanism after beam alignment, ensuring the mount's stability. However, this process can introduce errors, causing a drift in the optical path. To mitigate this issue, in this study, an interference fit adjustment screw was designed. This development enables the mechanism to self-lock after beam alignment, thereby preventing optical path drift and enhancing overall stability. Specifically, 14 long-term thermal shock stability tests, each lasting 2500 min, were conducted to validate the proposed design. The experimental results showed that the thermal drift of the interference fit adjustment screw was reduced by 47.16%, thermal shift was reduced by 79.59%, and the long-term stability improved by at least 48.67%.

A novel Fc-enhanced humanized monoclonal antibody targeting B7-H3 suppresses the growth of ESCC

Esophageal squamous cell carcinoma (ESCC) is a prevalent malignant tumor of the digestive tract with a low 5-year survival rate due to the lack of effective treatment methods. Although therapeutic monoclonal antibodies (mAbs) now play an important role in cancer therapy, effective targeted mAbs are still lacking for ESCC. B7-H3 is highly expressed in a variety of tumors and has emerged as a promising therapeutic target. Several mAbs against B7-H3 have advanced to clinical trials, but their development has not yet been pursued for ESCC. Here, we developed a humanized and Fc-engineered anti-B7H3 mAb 24F-Hu-mut2 and systematically evaluated its anti-tumor activity in vitro and in vivo. The 24F-Hu-mut2 was humanized and modified in Fc fragment to obtain stronger antibody-dependent cell-mediated cytotoxicity(ADCC) activity and nanomolar affinity. Furthermore, both of ESCC cell-derived xenograft (CDX) and patient-derived xenograft (PDX) mice models indicated that 24F-Hu-mut2 displayed potent in vivo anti-tumor activity. In addition, a computational docking model showed that the mAb bound to IgC1 and IgC2 domain of B7-H3, which is closer to the cell membrane. Consistently, our ELISA results verified the binding of 24F-Hu-WT and IgC1 and IgC2. Our results indicate that 24F-Hu-mut2 has significant anti-ESCC activity both in vitro and in vivo, and this monoclonal antibody may be a promising antibody against ESCC and other B7-H3 overexpressing tumors.

Gain optimization of an erbium-ytterbium co-doped amplifier via a Si3N4 photonic platform

Erbium-doped waveguide amplifiers enable the integration of various active functions on a silicon platform. Er3+ can provide the basis for efficient optical amplification of photonic integrated circuits, but the gain is limited by cooperative upconversion leading to doping concentration limitations and insufficient optimization of the waveguide structure. In this paper, an erbium-ytterbium co-doped Al2O3 amplifier has been innovatively implemented on a low loss Si3N4 waveguide by careful design and optimization with the finite difference method. A more accurate and comprehensive theoretical model of erbium-ytterbium co-doping is established, with consideration of upconversions, energy transfer, amplified spontaneous radiation and propagation loss to perform optimization of the high-gain erbium-ytterbium co-doped waveguide amplifier. The optimized waveguide amplifier achieves a small-signal gain of more than 36 dB at 1550 nm under Er3+ concentration of 3 × 1020 cm-3 and Yb3+ concentration of 3 × 1021 cm-3. Endowing Si3N4 photonic integrated circuits with gain can enable the miniaturization of various on-chip based active devices.

PGC-1α promotes colorectal carcinoma metastasis through regulating ABCA1 transcription

Colorectal cancer (CRC) is a highly aggressive cancer in which metastasis plays a key role. However, the mechanisms underlying metastasis have not been fully elucidated. Peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), a regulator of mitochondrial function, has been reported as a complicated factor in cancer. In this study, we found that PGC-1α was highly expressed in CRC tissues and was positively correlated with lymph node and liver metastasis. Subsequently, PGC-1α knockdown was shown to inhibit CRC growth and metastasis in both in vitro and in vivo studies. Transcriptomic analysis revealed that PGC-1α regulated ATP-binding cassette transporter 1 (ABCA1) mediated cholesterol efflux. Mechanistically, PGC-1α interacted with YY1 to promote ABCA1 transcription, resulting in cholesterol efflux, which subsequently promoted CRC metastasis through epithelial-to-mesenchymal transition (EMT). In addition, the study identified the natural compound isoliquiritigenin (ISL) as an inhibitor that targeted ABCA1 and significantly reduced CRC metastasis induced by PGC-1α. Overall, this study sheds light on how PGC-1α promotes CRC metastasis by regulating ABCA1-mediated cholesterol efflux, providing a basis for further research to inhibit CRC metastasis.

Diosmetin suppresses the progression of ESCC by CDK2/Rb/E2F2/RRM2 pathway and synergies with cisplatin

Cisplatin (CDDP) is the first-line drug in the clinical treatment of esophageal squamous cell carcinoma (ESCC), which has severe nephrotoxicity. Diosmetin (DIOS) can protect kidney from oxidative damage, however, its function in ESCC is unknown. This study aims to explore the effect and mechanism of DIOS on ESCC and its combined effect with CDDP. Herein, we found that DIOS significantly inhibited the progression of ESCC in vitro and in vivo. Furthermore, the anti-tumor effect of DIOS was not statistically different from that of CDDP. Mechanically, transcriptomics revealed that DIOS inhibited the E2F2/RRM2 signaling pathway. The transcriptional regulation of RRM2 by E2F2 was verified by luciferase assay. Moreover, docking model, CETSA, pull-down assay and CDK2 inhibitor assay confirmed that DIOS directly targeted CDK2, leading to significant suppression of ESCC. Additionally, the patient-derived xenografts (PDX) model showed that the combination of DIOS and CDDP significantly inhibited the growth of ESCC. Importantly, the combined treatment with DIOS and CDDP significantly reduced the mRNA expression levels of kidney injury biomarkers KIM-1 and NGAL in renal tissue, as well as the levels of blood urea nitrogen, serum creatinine and blood uric acid compared to the single treatment with CDDP. In conclusion, DIOS could be an effective drug and a potential chemotherapeutic adjuvant for ESCC treatment. Furthermore, DIOS could reduce the nephrotoxicity of CDDP to some extent.

TOPK promotes the growth of esophageal cancer in vitro and in vivo by enhancing YB1/eEF1A1 signal pathway

T-LAK-originated protein kinase (TOPK), a dual specificity serine/threonine kinase, is up-regulated and related to poor prognosis in many types of cancers. Y-box binding protein 1 (YB1) is a DNA/RNA binding protein and serves important roles in multiple cellular processes. Here, we reported that TOPK and YB1 were both highly expressed in esophageal cancer (EC) and correlated with poor prognosis. TOPK knockout effectively suppressed EC cell proliferation and these effects were reversible by rescuing YB1 expression. Notably, TOPK phosphorylated YB1 at Thr 89 (T89) and Ser 209 (S209) amino acid residues, then the phosphorylated YB1 bound with the promoter of the eukaryotic translation elongation factor 1 alpha 1 (eEF1A1) to activate its transcription. Consequently, the AKT/mTOR signal pathway was activated by up-regulated eEF1A1 protein. Importantly, TOPK inhibitor HI-TOPK-032 suppressed the EC cell proliferation and tumor growth by TOPK/YB1/eEF1A1 signal pathway in vitro and in vivo. Taken together, our study reveals that TOPK and YB1 are essential for the growth of EC, and TOPK inhibitors may be applied to retard cell proliferation in EC. This study highlights the promising therapeutic potential of TOPK as a target for treatment of EC.

PHGDH promotes esophageal squamous cell carcinoma progression via Wnt/β-catenin pathway

PURPOSE

Esophageal squamous carcinoma (ESCC) with a high incidence in China, lacks effective therapeutic targets. Phosphoglycerate dehydrogenase (PHGDH) is a key enzyme in serine biosynthesis. However, the biological role of PHGDH in ESCC has not been revealed.

METHODS

The expression of PHGDH in ESCC was investigated by UALCAN. The relationship between PHGDH expression and its prognostic value was analyzed by Kaplan-Meier and univariate Cox regression. Further, the potential functions of PHGDH involved in ESCC were explored through DAVID database and GSEA software. In addition, the expression of PHGDH was verified in ESCC. Then, the effects of PHGDH knockdown on ESCC were evaluated in vitro and in vivo by cell proliferation, clone formation, cell cycle, apoptosis, tube formation assays and ESCC cells derived xenograft model. In addition, western blotting and immunohistochemistry were used to detect the expression of Wnt/β-catenin pathway which was associated with PHGDH.

RESULTS

Bioinformatics analysis found that PHGDH was highly expressed in ESCC, and meaningfully, patients with high PHGDH expression had a poor prognosis. Moreover, the overexpression of PHGDH was verified in ESCC. Afterwards, PHGDH knockdown inhibited the cell proliferation, induced cell cycle arrest and apoptosis in ESCC cells, and inhibited the angiogenesis of HUVECs induced by ESCC conditioned medium, as well as inhibited the growth of xenograft tumor. Mechanistically, PHGDH knockdown inhibited Wnt/β-catenin signaling pathway in ESCC.

CONCLUSION

High expression of PHGDH predicts a poor prognosis for ESCC. PHGDH knockdown inhibits ESCC progression by suppressing Wnt/β-catenin signaling pathway, indicating that PHGDH might be a potential target for ESCC therapy.

Design and optimization of GI-PCF supporting the orbital angular momentum modes based on negative curvature structure

Based on the negative curvature structure, we design a graded-index photonic crystal fiber (GI-PCF) supporting the orbital angular momentum (OAM) mode transmission and discuss its optimization strategy. The core of the designed GI-PCF is sandwiched by three-layer inner air-hole arrays with gradually decreasing air-hole radii and a single outer air-hole array, where the inner side of the annular core forms a graded refractive index distribution. All these structures are clad with negative-curvature tubes. By optimizing characteristic structural parameters, including the air-filling fraction of the outer array, the air-hole radii of the inner arrays, and the thickness of the tubes, the GI-PCF can support 42 OAM modes and most of them have a purity greater than 85%. Compared with conventional structures, the present design of GI-PCF has better properties on an overall level, which can stably transmit multiple OAM modes with high mode purity. These results inject new interest in the flexible design of PCF and have potential applications in various fields, including but not limited to the mode division multiplexing system and terabit data transmission.

Tegaserod Maleate Suppresses the Growth of Gastric Cancer In Vivo and In Vitro by Targeting MEK1/2

Gastric cancer (GC) ranks fifth in global incidence and fourth in mortality. The current treatments for GC include surgery, chemotherapy and radiotherapy. Although treatment strategies for GC have been improved over the last decade, the overall five-year survival rate remains less than 30%. Therefore, there is an urgent need to find novel therapeutic or preventive strategies to increase GC patient survival rates. In the current study, we found that tegaserod maleate, an FDA-approved drug, inhibited the proliferation of gastric cancer cells, bound to MEK1/2 and suppressed MEK1/2 kinase activity. Moreover, tegaserod maleate inhibited the progress of gastric cancer by depending on MEK1/2. Notably, we found that tegaserod maleate suppressed tumor growth in the patient-derived gastric xenograft (PDX) model. We further compared the effect between tegaserod maleate and trametinib, which is a clinical MEK1/2 inhibitor, and confirmed that tegaserod maleate has the same effect as trametinib in inhibiting the growth of GC. Our findings suggest that tegaserod maleate inhibited GC proliferation by targeting MEK1/2.

Preliminary study on the role and mechanism of KIRREL3 in the development of esophageal squamous cell carcinoma

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is a common malignant tumor of the digestive tract, which is very harmful to human health. The JAK-STAT signaling pathway is a recognized carcinogenic pathway that plays a role in the proliferation, apoptosis, migration, and invasion of a variety of cancer cells. Some studies have shown that the activation status of STAT3 affects the expression of KIRREL3. However, the expression of KIRREL3 in ESCC and its relationship with KIRREL3 or the JAK-STAT signaling pathway is still unclear.

METHODS

In this study, we used immunohistochemistry and western blotting to analyze the protein expression levels of KIRREL3 in tumor tissues and ESCC cell lines. We applied proliferation assays, plate clone formation assays, Transwell assays, flow cytometry analysis, and CDX animal models to examine the role of KIRREL3 in ESCC.

RESULTS

The results indicate that KIRREL3 is highly expressed to varying degrees in ESCC tissues and cell lines. Knocking down KIRREL3 expression in ESCC cells could correspondingly inhibit cell proliferation, colony formation, invasion, and migration, and had some effects on cell cycle progression and apoptosis. In addition, overexpressing KIRREL3 in these cells had opposite effects. Tumor formation in nude mice experiments also confirmed that KIRREL3 is involved in the growth of ESCC cells in vivo.

CONCLUSIONS

These data suggest that KIRREL3 plays a key role in the development of ESCC, and KIRREL3 is a potential new target for the early diagnosis and clinical treatment of this disease.

Immunogenomic Landscape Analysis of Prognostic Immune-Related Genes in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death. HBV infection is an important risk factor for the tumorigenesis of HCC, given that the inflammatory environment is closely related to morbidity and prognosis. Consequently, it is of urgent importance to explore the immunogenomic landscape to supplement the prognosis of HCC. The expression profiles of immune-related genes (IRGs) were integrated with 377 HCC patients to generate differentially expressed IRGs based on the Cancer Genome Atlas (TCGA) dataset. These IRGs were evaluated and assessed in terms of their diagnostic and prognostic values. A total of 32 differentially expressed immune-related genes resulted as significantly correlated with the overall survival of HCC patients. The Gene Ontology functional enrichment analysis revealed that these genes were actively involved in cytokine-cytokine receptor interaction. A prognostic signature based on IRGs (HSPA4, PSME3, PSMD14, FABP6, ISG20L2, TRAF3, NDRG1, NRAS, CSPG5, and IL17D) stratified patients into high-risk versus low-risk groups in terms of overall survival and remained as an independent prognostic factor in multivariate analyses after adjusting for clinical and pathologic factors. Several IRGs (HSPA4, PSME3, PSMD14, FABP6, ISG20L2, TRAF3, NDRG1, NRAS, CSPG5, and IL17D) of clinical significance were screened in the present study, revealing that the proposed clinical-immune signature is a promising risk score for predicting the prognosis of HCC.

AGT serves as a potential biomarker and drives tumor progression in colorectal carcinoma

BACKGROUND

Colorectal carcinoma (CRC) is one of the most common aggressive tumors worldwide, and it is necessary to identify candidate biomarkers and therapeutic targets in CRC to improve patient outcomes.

METHODS

The differentially expressed genes (DEGs) were obtained from CRC microarray. Functional enrichment was performed to explore the function of DEGs, and core genes were identified by Cytoscape. Then, the diagnosis and prognosis markers were identified by ROC curve and survival analyses. More importantly, a series of in vitro studies were conducted in CRC cells to explore the function of the selected biomarker. Further, the drug response was performed by Cancer Cell Line Encyclopedia (CCLE) and Cancer Therapy Response Portal (CTRP). In addition, the effect of drug on CRC cells was evaluated by functional experiments.

RESULTS

The identified DEGs were mainly associated with the processes relating to tumorigenesis. 25 core genes were selected and angiotensinogen (AGT) was filtered out as a diagnosis and prognosis biomarker. Comprehensive in vitro experiments showed that AGT attributed to the proliferation, migration, and invasion of CRC cells, as well as angiogenesis of HUVECs induced by CRC conditional medium. Furthermore, drug response analysis implied that AGT expression was associated with isoliquiritigenins (ISL). Additionally, ISL could suppress the progression of CRC cells.

CONCLUSIONS

AGT is identified as diagnosis and prognosis prediction of CRC. Moreover, AGT attributes to the progression of CRC. Additionally, AGT exhibits fine drug response to ISL, and ISL is also evaluated as potential therapy drug in CRC.

DNA polymerase β deficiency promotes the occurrence of esophageal precancerous lesions in mice

Esophageal mucosa undergoes mild, moderate, severe dysplasia, and other precancerous lesions and eventually develops into carcinoma in situ, and understanding the developmental progress of esophageal precancerous lesions is beneficial to prevent them from developing into cancer. DNA polymerase β (Polβ), a crucial enzyme of the base excision repair system, plays an important role in repairing damaged DNA and maintaining genomic stability. Abnormal expression or deletion mutation of Polβ is related to the occurrence of esophageal cancer, but the role of Polβ deficiency in the esophageal precancerous lesions is still unclear. Here, esophageal mucosa Polβ-knockout mice were used to explore the relationship of Polβ deficiency with esophageal precancerous lesions. First, we found the degree and number of esophageal precancerous lesions in Polβ-KO mice were more serious than those in Polβ-Loxp mice after N-nitrosomethylbenzylamine (NMBA) treatment. Whole exome sequencing revealed that deletion of Polβ increased the frequency of gene mutations. Gene expression prolife analysis showed that the expression of proteins correlated to cell proliferation and the cell cycle was elevated in Polβ-KO mice. We also found that deletion of Polβ promoted the proliferation and clone formation as well as accelerated cell cycle progression of human immortalized esophageal epithelial cell line SHEE treated with NMBA. Our findings indicate that Polβ knockout promotes the occurrence of esophageal precancerous lesions.

Allogenic mouse cell vaccine inhibits lung cancer progression by inhibiting angiogenesis

Aim: This research investigated the therapeutic effect of an allogeneic mouse brain microvascular endothelial cell vaccine on lung cancer and further elucidated its potential anti-angiogenic mechanism. Materials & methods: The immune effect of the allogeneic bEnd.3 vaccine and DC vaccine loaded with bEnd.3 antigen on the subcutaneous transplantation of Lewis lung cancer (LLC) was assessed by ELISA, the CCK test and the CTL killing test. The mechanism was preliminarily revealed by immunohistochemistry and immunoblot analysis. Results: This study revealed that tumor volume was decreased (p < .01) and the survival was prolonged significantly (p < .05) by the bEnd.3 vaccine in subcutaneous LLC transplantation in the vaccine prevention group. In contrast, both tumor volume in the serum therapeutic group and survival of bEnd.3 vaccine were not significantly different from those of the control group (p > .05). Importantly, tumor volume and survival of the T lymphocyte therapeutic group were decreased and prolonged (p < .05). In addition, both tumor volume and survival of DC vaccine loaded with bEnd.3 in the vaccine prevention group were decreased and prolonged significantly (p < .01). Furthermore, bEnd.3 vaccine and DC vaccine loaded with bEnd.3 both produced the activity of killing bEnd.3 target cells in vitro.The reason may induce the immune mice to produce anti-VEGFR-II, anti-endoglin and anti-integrin αν antibodies to have an anti-angiogenesis function. Conclusion: The allogeneic mouse bEnd.3 cell vaccine can block angiogenesis and prevent the development of lung cancer transplantation tumors.

p21-activated kinase 4 promotes the progression of esophageal squamous cell carcinoma by targeting LASP1

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignant tumors of the digestive tract in humans. Several studies have indicated that PAK4 is associated with the risk of ESCC and may be a potential druggable kinase for ESCC treatment. However, the underlying mechanism remains largely unknown. The aim of our study is to identify the functional role of PAK4 in ESCC. To determine the expression of PAK4 in ESCC, Western blot analysis and immunohistochemistry were performed, and the results showed that PAK4 is significantly upregulated in ESCC tissues and cell lines compared with normal controls and normal esophageal epithelial cell line. To further investigate the role of PAK4 in ESCC, cell viability assays, anchorage-independent cell growth assays, wound healing assays, cellular invasion assays, in vivo xenograft mouse models, and metastasis assays were conducted, and the results showed that PAK4 can significantly facilitate ESCC proliferation and metastasis in vitro and in vivo. To determine the potential target of PAK4 in ESCC progression, a pull-down assay was performed, and the results showed that LASP1 may be a potential target of PAK4. An immunoprecipitation assay and confocal microscopy analysis confirmed that PAK4 can bind to and colocalize with LASP1 in vitro and in cells. Notably, rescue experiments further illustrated the mechanistic network of PAK4/LASP1. Our research reveals the oncogenic roles of PAK4 in ESCC and preliminarily elucidates the mechanistic network of PAK4/LASP1 in ESCC.

Dihydroartemisinin Inhibits the Proliferation of Esophageal Squamous Cell Carcinoma Partially by Targeting AKT1 and p70S6K

Dihydroartemisinin (DHA), a sesquiterpene lactone with endoperoxide bridge, is one of the derivatives of artemisinin. In addition to having good antimalarial properties, DHA exhibits anticancer effects including against malignant solid tumors. However, the mechanism by which DHA inhibits the progression of esophageal cancer, especially esophageal squamous cell carcinoma (ESCC), is unclear. In this study, DHA was found to inhibit the proliferation of ESCC, and the underlying molecular mechanisms were explored. DHA inhibited ESCC cells proliferation and anchorage-independent growth. Flow cytometry analysis revealed that DHA significantly blocked cell cycle in the G1 phase. The results of human phospho-kinase array revealed that DHA downregulated the levels of p70S6K^T389 and p70S6K^T421/S424. Furthermore, the levels of mTOR^S2448, p70S6K^T389, p70S6K^T421/S424 and RPS6^S235/S236 were decreased after DHA treatment in KYSE30 and KYSE150 cells. We then explored the proteins targeted by DHA to inhibit the mTOR-p70S6K-RPS6 pathway. Results of the in vitro kinase assay revealed that DHA significantly inhibited phosphorylation of mTOR^S2448 by binding to AKT1 and p70S6K kinases. In vivo, DHA inhibited the tumor growth of ESCC patient-derived xenografts and weakened p-mTOR, p-p70S6K, and p-RPS6 expression in tumor tissues. Altogether, our results indicate that DHA has antiproliferative effects in ESCC cells and can downregulate mTOR cascade pathway partially by binding to AKT1 and p70S6K. Thus, DHA has considerable potential for the prevention or treatment of ESCC.

Proteomics Reveal the Inhibitory Mechanism of Levodopa Against Esophageal Squamous Cell Carcinoma

High recurrence rates and poor survival of patients with esophageal squamous cell carcinoma (ESCC) after treatment make ongoing research on chemoprevention drugs for ESCC particularly important. In this study, we screened a large number of FDA-approved drugs and found levodopa, a drug used to treat Parkinson's disease, had an inhibitory effect on the growth of ESCC cells. To elucidate the molecular mechanisms involved, we applied quantitative proteomics to investigate the anti-tumor activity of levodopa on ESCC. The results suggest that levodopa could down-regulate oxidative phosphorylation, non-alcoholic fatty liver disease, and Parkinson's disease pathways. Major mitochondrial respiratory compounds were involved in the pathways, including succinate dehydrogenase subunit D, NADH-ubiquinone oxidoreductase Fe-S protein 4, and mitochondrial cytochrome c oxidase subunit 3. Down-regulation of these proteins was associated with mitochondrial dysfunction. Western blotting and immunofluorescence results confirmed the proteomics findings. Cell viability assays indicated mitochondrial activity was suppressed after levodopa treatment. Reduced mitochondrial membrane potential was detected using JC-1 staining and TMRE assays. Transmission electron microscopy revealed changes in the morphology of mitochondria. Taken together, these results indicate that levodopa inhibited the growth of ESCC through restraining mitochondria function.

Retraction Note: Mir-655 up-regulation suppresses cell invasion by targeting pituitary tumor-transforming gene-1 in esophageal squamous cell carcinoma

The Editor-in-Chief has retracted this article [1] because Figure 3a overlaps with Figure 2 in [2]. An investigation by Zhengzhou University has confirmed this. The data reported in this article are therefore unreliable. There is also considerable text overlap with a previously published article [3]. Guoqiang Zhao does not agree with this retraction. The other authors have not responded to correspondence from the editor about this retraction.

Correction to: TOPK promotes metastasis of esophageal squamous cell carcinoma by activating the Src/GSK3β/STAT3 signaling pathway via γ-catenin

Following publication of the original article [1], the authors reported the errors in Fig. 1C and D, Fig. 2, Fig. 4B and C and Fig. 6D and E.

[Joint effect of smoking and diabetes on stroke]

Objective: To explore the interaction of smoking and diabetes on stroke. Methods: In this case-control study, a face to face questionnaire survey was conducted. Logistic regression models were used to analyze the relationship between smoking or diabetes and stroke. The indicators of interaction were calculated according to the Bootstrap method in this study. Results: A total of 918 cases and 918 healthy controls, who participated in the chronic disease risk factor survey in Xuzhou in 2013, were included in this study. Logistic regression analysis found that cigarette smoking was associated with stroke (OR=1.63, 95%CI: 1.33-2.00), and diabetes was also associated with stroke (OR=2.75, 95%CI: 2.03-3.73) after adjusting confounders. Compared with those without diabetes and smoking habit, the odds ratio of stroke in those with diabetes and smoking habits was 8.94 (95%CI:3.77-21.19). Diabetes and smoking combined interaction index was 3.65 (95%CI: 1.68-7.94), the relative excess risk was 5.77 (95%CI: 0.49-11.04), the attributable proportion was 0.65 (95%CI: 0.42-0.87). Conclusion: The results suggest that there are additive interactions between smoking and diabetes on stroke.

The natural polyphenol curcumin induces apoptosis by suppressing STAT3 signaling in esophageal squamous cell carcinoma

Background

We and others have previously shown that the STAT3 signaling pathway is activated in some esophageal squamous cell carcinoma (ESCC) cells and is required for the survival and growth of these primary ESCC-derived xenografts. It has also been shown that the natural polyphenol curcumin is an effective anti-tumor agent.

Methods

Luciferase assay and immunoblotting were performed to examine whether curcumin suppressed STAT3 signaling. CCK-8 assay and xenografts were utilized for analyzing ESCC cell growth in culture and mice. Soft agar assay was carried out to determine the colony formation ability of ESCC cells in the presence or absence of curcumin. Cell death and cell cycle were assessed by In CELL Analyzer 2000. Immunohistochemistry and TUNEL assay were used for detecting apoptosis in ESCC tisuses. Molecular docking was performed to evaluate the interaction of curcumin with JAK2. JAK2 activity was assessed using an in vitro cell-free system. HE staining was used to evaluate the ESCC tissues.

Results

The natural polyphenol curcumin inhibited STAT3 phosphorylation rapidly and blocked STAT3-mediated signaling in ESCC cells. It also induced growth arrest and apoptosis in cultured ESCC cells, which were attenuated by enforced expression of STAT3. Furthermore, curcumin preferentially blocked the growth of primary ESCC-derived xenografts that harbored activated STAT3.

Conclusions

Curcumin is able to exert anti-tumor action through inhibiting the STAT3 signaling pathway. Giving its wide use in traditional medicines with low toxicity and few adverse reactions, it is conceivable that curcumin might be further explored as a unique STAT3 inhibitor for anti-cancer therapies.

Aloe emodin suppresses EGF‑induced neoplastic cell transformation by inhibiting the ERK/MSK1 and AKT/GSK3β signaling pathways

Natural compounds which can block cell transformation due to potential for chemoprevention have received increased attention. The present study aimed to investigate whether aloe emodin, which is present in aloe latex or the roots of the Rheum palmatum L. are able to block epidermal growth factor (EGF)‑ and tissue plasminogen activator‑induced JB6 C141 cell transformation. The aloe emodin treatment was applied to the JB6 C141 cell neoplastic model. The toxicity of aloe emodin was determined. The present study detected the expression level of AKT serine/threonine kinase 1 (AKT), lysine‑tRNA ligase MSK1 (MSK1) and cyclin D1 using western blotting. The cell proliferation and cell cycle distribution were also monitored. And when 95‑maximal effective dose ranged between 1 and 15 µM, the cell death was evident. Aloe emodin‑treated cells had an impaired anchorage‑independent growth capability, leading to a dose‑dependent reduction of colony formation. Western blotting revealed that aloe emodin had a significant effect on phosphorylation of pyruvate dehydrogenase kinase 1 and glycogen synthase kinase 3β (GSK3β) and AKT was inhibited. The present study determined that the proliferation of JB6 C141 cells was reduced in a dose‑dependent manner and the effect may be associated with its inhibition of the G1/S cell cycle transition. Cyclin D1 transcriptional activity was reduced to 25%, 24 h following aloe emodin treatment. The protein expression of cyclin D1 was inhibited. The findings of the present study indicated that aloe emodin may be able to suppress neoplastic cell transformation by inhibiting the extracellular‑signal regulated kinase/MSK1 and AKT/GSK3β signaling pathways. It may be a potential natural compound for chemoprevention.

Targeting the overexpressed USP7 inhibits esophageal squamous cell carcinoma cell growth by inducing NOXA-mediated apoptosis

Increasing evidence suggests that deubiquitinase USP7 participates in tumor progression by various mechanisms and serves as a potential therapeutic target. However, its expression and role in esophageal cancer remains elusive; the anti-cancer effect by targeting USP7 still needs to be investigated. Here, we reported that USP7 was overexpressed in esophageal squamous cell carcinoma (ESCC) tissues compared with adjacent tissues, implying that USP7 was an attractive anticancer target of ESCC. Pharmaceutical or genetic inactivation of USP7 inhibited esophageal cancer cells growth in vitro and in vivo and induced apoptosis. Mechanistically, inhibition of USP7 accumulated poly-ubiquitinated proteins, activated endoplasmic reticulum stress, and increased expression of ATF4, which transcriptionally upregulated expression of NOXA and induced NOXA-mediated apoptosis. These results provide an evidence for clinical investigation of USP7 inhibitors for the treatment of ESCC.

General self-efficacy modifies the effect of stress on burnout in nurses with different personality types

Background

Burnout is a health problem in nurses. Individuals with a certain personality are more susceptible to job-related burnout. General self-efficacy (GSE) is an important predictor of job-related burnout. The relationships between general self-efficacy, job-related burnout and different personality types are still not clear. This study aims to analyze the relationships of job-related burnout, stress, general self-efficacy and personality types, as well as their interactions in job-related burnout.

Method

A cross-sectional survey of 860 nurses was conducted between June and July 2015 in China. We measured their job-related burnout using the scale of the Maslach Occupational Burnout Scale, and personality, stress, and GSE. Machine learning of generalized linear model were performed.

Results

Maslach Burnout Inventory (MBI) professional efficacy was significantly associated with gender, marital status, age, job title and length of service. A machine learning algorithm showed that stress was the most important factor in job-related burnout, followed by GSE, personality type (introvert unstable), and job title. Individuals with low GSE and either introversion or unstable (high neuroticism) personality seemed to have stronger burnout when they faced stress (regardless of stress intensity) compared to others.

Conclusion

Stress, GSE and introvert unstable personality are the top three factors of job-related burnout. GSE moderates the effect of stress on burnout in nurses with extroversion or neuroticism personality. Reducing stress, increasing GSE, and more social support may alleviate job-related burnout in nurses. Nurses with introvert unstable personality should be given more social support in reducing stress and enhancing their GSE.

Electronic supplementary material

The online version of this article (10.1186/s12913-018-3478-y) contains supplementary material, which is available to authorized users.

Human umbilical vein endothelial cell vaccine suppresses the angiogenesis of esophageal squamous cell carcinoma in a humanized mouse model

The antitumor effect of the human umbilical vein endothelial cell (HUVEC) vaccine has been well documented; however, its anti‑angiogenic effects on human esophageal squamous cell carcinoma (ESCC) have yet to be studied. In the present study, a 'humanized' mouse model was established by transplanting NOD/SCID mice with human peripheral blood mononuclear cells (PBMC). After 4 weeks, the level of cluster of differentiation (CD)‑45+ human T‑lymphocytes in mouse peripheral blood was >0.1%, which indicated that mouse reconstruction and the human immune system transformation had been successful. The humanized mice were used to evaluate the anti‑angiogenic effect of the HUVEC vaccine on human ESCC. After immunization with the HUVEC vaccine for 5 consecutive weeks, the humanized mice were subcutaneously transplanted with EC9706 cells. The results indicated that the HUVEC vaccine reduced the size of human esophageal carcinoma xenografts by suppressing angiogenesis. In addition, the HUVEC‑immunized mice exhibited reduced expression of angiogenesis‑associated antigens (vascular endothelial growth factor receptor 2 and VE‑Cadherin) in the tumor specimens, and increased levels of angiogenesis‑associated antibodies in the serum. Notably, the HUVEC vaccine also increased the infiltration of human T‑lymphocytes into the spleen of humanized mice. In conclusion, the present study demonstrated the anti‑angiogenic effect of the HUVEC vaccine on ESCC in a humanized mouse model, and set an experimental foundation for the application of the HUVEC vaccine in ESCC patients.

Establishment of lung cancer patient-derived xenograft models and primary cell lines for lung cancer study

Background

The overall 5-year survival rate of lung cancer is about 15% even with therapeutic drugs like tyrosine kinase inhibitors. Ideal models are urgently needed for exploring mechanisms and finding new drugs. Patient-derived xenografts (PDX) models and primary cells are both used to screen therapeutic regimens for cancer. However, PDX models and primary cells from the same patient are difficult to establish. Their consistency to the original tumor tissue is not well studied.

Methods

31 lung cancer patient tissues were procured to establish the lung cancer PDX models and primary cell lines. Tumor growth measurements, histological and immunohistochemistry analysis, Western blotting, EGFR and K-RAS mutation detection and gefitinib sensitive assay were performed to evaluate the characteristic of established PDX models. Immunofluorescence analysis, anchorage-independent cell growth, Western blotting and gefitinib sensitive assay were performed to assay the characteristic of established primary cell lines. The whole-exome sequencing was used to compare the characteristic of the patient’s tumor tissue, established PDX and primary cell line.

Results

Twenty-one lung cancer PDX models (67.74%, 21/31) and ten primary cell lines (32.25%, 10/31) were established from patients’ tumor tissues. The histology and pathological immunohistochemistry of PDX xenografts are consistent with the patients’ tumor samples. Various signal pathways were activated in different PDX models (n = 5) and primary cell lines (n = 2). EGFR mutation PDX model and primary cell line (LG1) were sensitive to gefitinib treatment. The expression of CK8/18, TTF1 and NapsinA in LG1 and LG50 primary cells were also positive. And the activated signal pathways were activated in LG1 and LG50 primary cell lines. Furthermore, the gene mutation in PDX tumor tissues and primary cell line (LG50) was consistent with the mutation in LG50 patient’s tumor tissues.

Conclusion

These data suggested that established lung cancer PDX models and primary cell lines reserved mostly molecular characteristics of primary lung cancer and could provide a new tool to further understand the mechanisms and explore new therapeutic strategies.

Efficacy for lung metastasis induced by the allogeneic bEnd3 vaccine in mice

BACKGROUND

The mouse brain microvascular endothelial cell line bEnd.3 was used to develop a vaccine and its anti-tumor effect on lung metastases was observed in immunized mice.

METHODS

Mouse bEnd.3 cells cultured in-vitro and then fixed with glutaraldehyde was used to immunize mice; mice were challenged with the metastatic cancer cell line U14, and changes in metastatic cancer tissues were observed through hematoxylin and eosin staining. Carboxyfluorescein succinimidyl amino ester (CSFE) and propidium iodide (PI) were used to detect cytotoxic activity of spleen T lymphocytes; the ratio of CD3⁺ and CD8⁺ T-cell sub-sets was determined by flow cytometry. Enzyme-linked immunosorbent assay (ELISA), immunocytochemistry and immunoblot were used to examine the specific response of the antisera of immunized mice.

RESULTS

The number of metastatic nodules in bEnd.3 and human umbilical vein endothelial cell (HUVEC) vaccine groups was less than NIH3T3 vaccine group and phosphate buffered saline (PBS) control group. The bEnd.3-induced and HUVEC-induced cytotoxic T-lymphocytes (CTLs) showed significant lytic activity against bEnd.3 and HUVEC target cells, while the antisera of mice in bEnd.3 and HUVEC vaccine groups showed specific immune responses to membrane proteins and inhibited target cell proliferation in-vitro. Immunoblot results showed specific bands at 180KD and 220KD in bEnd.3 and at 130 kD and 220 kD in HUVEC lysates.

CONCLUSIONS

Allogeneic bEnd.3 vaccine induced an active and specific immune response to tumor vascular endothelial cells that resulted in production of antibodies against the proliferation antigens VEGF-R II, integrin, Endog etc. Immunization with this vaccine inhibited lung metastasis of cervical cancer U14 cells and prolonged the survival of these mice.

MiR-149 sensitizes esophageal cancer cell lines to cisplatin by targeting DNA polymerase β

Human DNA polymerase β (polβ) is a small, monomeric protein essential for short‐patch base excision repair (BER). polβ plays an important role in the regulation of chemotherapy sensitivity in tumour cells. In this study, we determined that the expression levels of polβ mRNA and miR‐149 in tumour tissues were significantly higher than in adjacent non‐tumour tissues. We also found that the expression level of miR‐149 in EC tumour tissues was inverse to that of polβ expression. Bioinformatics analysis and dual‐luciferase reporter assay predicted that miR‐149 negatively regulates polβ expression by directly binding to its 3′UTR. CCK‐8 assay indicated that miR‐149 could enhance the anti‐proliferative effects of cisplatin in EC1 and EC9706 cell lines. Flow cytometry, caspase 3/7 activity, and immunofluorescence microscopy results indicated that miR‐149 could enhance the apoptotic effects of cisplatin in EC1 and EC9706 cell lines. We also showed that the expression of polβ lacking the 3′UTR sequence could override the proliferative and apoptotic functions of miR‐149, suggesting that miR‐149 negatively regulates polβ expression by binding to its 3′UTR. Surface plasmon resonance results also showed that miR‐149 could bind with wild‐type polβ. In addition, we identified a new variant of polβ (C1134G). In conclusion, this study confirms that miR‐149 may enhance the sensitivity of EC cell lines to cisplatin by targeting polβ, and that miR‐149 may be unable to regulate the C1134G variant of polβ. Based on these findings, potential drugs could be developed with a focus on enhanced sensitivity of EC patients to chemotherapy.

Eupatilin inhibits the proliferation of human esophageal cancer TE1 cells by targeting the Akt‑GSK3β and MAPK/ERK signaling cascades

Eupatilin, a type of flavonoid compound, has potential anti‑inflammatory and antitumor roles in gastric cancer and endometrial cancer; however, the effect of eupatilin on human esophageal cancer and the underlying molecular mechanisms remain unclear. In the present study, we investigated the antitumor effect of eupatilin on human esophageal cancer cells in vitro and in vivo. We found that eupatilin inhibited the proliferation and colony formation of esophageal cancer TE1 cells. DNA content analysis showed that eupatilin induced cell cycle arrest of TE1 cells at the G0/G1 phase. In addition, our results suggested that eupatilin suppressed TE1 cell proliferation by targeting the Akt/GSK3β and MAPK/ERK signaling cascades. Furthermore, treatment with eupatilin was found to decrease tumor volume in a TE1 xenograft mouse model, and the phosphorylation of Akt and ERK1/2 was inhibited by eupatilin in the tumor tissue. Notably, no obvious weight loss for the mice was detected. In conclusion, the present results indicate that the antiproliferative effect of eupatilin on esophageal cancer TE1 cells is associated with inhibition of the Akt and ERK pathways.

Targeting the overexpressed ROC1 induces G2 cell cycle arrest and apoptosis in esophageal cancer cells

Recent reports showed that regulator of Cullins-1 (ROC1) play an important role in tumor progression in a tumor-specific manner. However, the role and mechanism of ROC1 in esophageal cancer remains elusive. Here we demonstrated that ROC1 was overexpressed in esophageal squamous cell carcinomas, which was positive associated with poor prognosis of esophageal cancer patients. ROC1 knockdown significantly inhibited the growth of esophageal cancer cells in vitro and in vivo. Mechanistically, ROC1 silencing induced G2 cell cycle arrest and triggered apoptosis by accumulating the pro-apoptotic protein NOXA. Consistently, the downregulation of NOXA expression via siRNA substantially attenuated apoptosis induced by ROC1 silencing. These findings suggest that ROC1 is an appealing drug target for esophageal cancer.

Knockdown of long non-coding RNA TP73-AS1 inhibits cell proliferation and induces apoptosis in esophageal squamous cell carcinoma

Recent studies have shown that long non-coding RNAs (lncRNAs) are involved in a variety of biological processes and diseases in humans, including cancer. Our study serves as the first comprehensive analysis of lncRNA TP73-AS1 in esophageal cancer. We utilized a lncRNA microarray to analyze the expression profile of lncRNAs in esophageal squamous cell carcinoma. Our results show that lncRNA TP73-AS1 and BDH2 levels are generally upregulated in esophageal cancer tissues and are strongly correlated with tumor location or TNM stage in clinical samples. LncRNA TP73-AS1 knockdown inhibited BDH2 expression in EC9706 and KYSE30 cells, whereas BDH2 knockdown repressed esophageal cancer cell proliferation and induced apoptosis via the caspase-3 dependent apoptotic pathway. Overexpression of BDH2 in lncRNA TP73-AS1 knockdown cells partially rescued cell proliferation rates and suppressed apoptosis. In mouse xenografts, tumor size was reduced in lncRNA TP73-ASI siRNA-transfected tumors, suggesting that downregulation of lncRNA TP73-AS1 attenuated EC proliferation in vitro and in vivo. In addition, BDH2 or lncRNA TP73-AS1 knockdown enhanced the chemosensitivity of esophageal cancer cells to 5-FU and cisplatin. Our results suggest that lncRNA TP73-AS1 may be a novel prognostic biomarker that could serve as a potential therapeutic target for the treatment of esophageal cancer.

Neddylation inhibitor MLN4924 induces G2 cell cycle arrest, DNA damage and sensitizes esophageal squamous cell carcinoma cells to cisplatin

Inhibiting the protein neddylation pathway using the NEDD8-activating enzyme inhibitor MLN4924 represents an attractive anticancer strategy having been demonstrated to exhibit promising anticancer efficacy and with tolerable levels of toxicity; however, the mechanism by which MLN4924 inhibits cell proliferation in human esophageal squamous cell carcinoma (ESCC) cells requires further investigation. The present study revealed that MLN4924 treatment led to G₂ cell cycle arrest and enhanced the protein stability of Wee1-like protein kinase and cyclin dependent protein kinase inhibitor 1A and B and p27. Furthermore, MLN4924 induced DNA damage and sensitized esophageal cancer cells to cisplatin by enhancing apoptosis. These findings extend the understanding of the function and mechanism of MLN4924 in ESCC and provide further evidence for the future development of neddylation inhibitors in clinical trials of esophageal cancer therapy, either alone or in combination.

Targeting Overexpressed Activating Transcription Factor 1 (ATF1) Inhibits Proliferation and Migration and Enhances Sensitivity to Paclitaxel In Esophageal Cancer Cells

Background

Previous reports showed that Activating Transcription Factor 1 (ATF1) plays an important role in tumor progression in a tumor-specific manner. However, little is known about the expression and role of ATF1 in esophageal cancer.

Material/Methods

The expression of ATF1 was examined by immunohistochemistry and Western blotting. The correlation between the expression of ATF1 and clinical characteristics of esophageal squamous cell carcinomas (ESCC) patients was analyzed by Fisher’s exact test. The role of cell proliferation, clonogenic survival, migration, and invasion in vitro, as well as the sensitization to paclitaxel, were determined after knockdown of ATF1 by siRNA.

Results

ATF1 was overexpressed in ESCC tissues, which was positively correlated with lymph node metastasis, poor differentiation, and early tumor invasion of esophageal cancer patients. Knockdown of ATF1 effectively reduced cell proliferation, induced S phase cell cycle arrest, and inhibited cell migration and invasion. Moreover, silencing of ATF1 significantly enhanced the sensitivity of esophageal cancer cells to paclitaxel.

Conclusions

These findings suggest that ATF1 is a promising drug target for esophageal cancer.

Constitutive activated STAT3 is an essential regulator and therapeutic target in esophageal squamous cell carcinoma

Esophageal carcinoma is among the most common cancers worldwide and a leading cause of cancer death [1]. Large numbers of studies indicated that chronic inflammation is closely associated with its development [21, 25]. Furthermore, the JAK/STAT pathway, which plays a critical role in inflammation and immunity, has been implied in a number of malignancies [11]. It has been shown that targeting the pathway affected the growth, apoptosis, and metastasis of cultured esophageal squamous cell carcinoma cells [26]. We found in the present study that STAT3 is constitutively activated in a subgroup of esophageal squamous cell carcinoma cell lines and primary tumors. Altered expressions of STAT3 target genes were found in these tumors by using RNAseq and qPCR analysis. Cytokines that activate STAT3 affected the expression of STAT3 target genes and promoted the growth of the ESCC cells, which could be blocked by STAT3 inhibitor and specific siRNA. Inhibition of STAT3 also suppressed the growth and colony formation, and induced apoptosis in the esophageal squamous cell carcinoma cells containing constitutively activated STAT3. Furthermore, the STAT3 inhibitor effectively blocked the growth of patient-derived tumor xenografts that harbored phosphorylated STAT3, but acted less effective on the xenografts derived from primary tumors that contained low levels of activated STAT3. These results indicated that activated STAT3 plays a critical role in the survival and growth of a subgroup of esophageal squamous cell carcinoma, and may serve as a target for precision therapeutic intervention.

Metformin inhibits esophageal squamous cell carcinoma-induced angiogenesis by suppressing JAK/STAT3 signaling pathway

Although it has been known that the tumor microenvironment affects angiogenesis, the precise mechanism remains unclear. In this study, we simulated the microenvironment of human esophageal squamous cell carcinoma (ESCC) by tumor conditioned medium (TCM) to assess the influence on normal endothelial cells (NECs). We found that the TCM-induced NECs showed enhanced angiogenic properties, such as migration, invasion and tube formation. Moreover, the TCM-induced NECs expressed tumor endothelial cells (TECs) markers at higher levels, which indicated that TCM probably promoted tumor angiogenesis by coercing NECs to change toward TECs. The microarray gene expression analysis indicated that TCM induced great changes in the genome of NECs and altered many regulatory networks, especially c-MYC and JAK/STAT3 signaling pathway. More importantly, we investigated the anti-angiogenic effect of metformin, and found that metformin abrogated the ESCC microenvironment-induced transition of NECs toward TECs by inhibiting JAK/STAT3/c-MYC signaling pathway. Furthermore, we verified the anti-angiogenic activity of metformin in vivo by a human ESCC patient-derived xenograft (PDX) mouse model for the first time. Taken together, our research provides a novel mechanism for the anti-angiogenic effect of metformin, and sets an experimental basis for the development of new anti-angiogenic drugs by blocking the transition of NECs toward TECs, which possibly open new avenues for targeted treatment of cancer.

Abstract 7: Ceftriaxone, an FDA-approved cephalosporin antibiotic, suppresses lung cancer growth by targeting Aurora B

Ceftriaxone, an FDA-approved third-generation cephalosporin antibiotic, has antimicrobial activity against both gram-positive and gram-negative organisms. Generally, ceftriaxone is used for a variety of infections such as community-acquired pneumonia, meningitis and gonorrhea. Its primary molecular targets are the penicillin-binding proteins. However, other activities of ceftriaxone remain unknown. Herein, we report for the first time that ceftriaxone has antitumor activity in vitro and in vivo. Kinase profiling results predicted that Aurora B might be a potential ‘off’ target of ceftriaxone. Pull-down assay data confirmed that ceftriaxone could bind with Aurora B in vitro and in A549 cells. Furthermore, ceftriaxone (500 µM) suppressed anchorage-independent cell growth by targeting Aurora B in A549, H520 and H1650 lung cancer cells. Importantly, in vivo xenograft animal model results showed that ceftriaxone effectively suppressed A549 and H520 lung tumor growth by inhibiting Aurora B. These data suggest the anticancer efficacy of ceftriaxone for the treatment of lung cancers through its inhibition of Aurora B.

Citation Format: Xiang Li, Haitao Li, Shengqing Li, Feng Zhu, Dong Joon Kim, Hua Xie, Yan Li, Janos Nadas, Naomi Oi, Tatyana Zykova, Dong Hoon Yu, Mee-Hyun Lee, Myoung Ok Kim, Lei Wang, Wei Ya Ma, Ronald A. Lubet, Ann M. Bode, Ziming Dong, Zigang Dong. Ceftriaxone, an FDA-approved cephalosporin antibiotic, suppresses lung cancer growth by targeting Aurora B [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 7. doi:10.1158/1538-7445.AM2017-7

Histone deacetylase inhibitor trichostatin A enhances the antitumor effect of the oncolytic adenovirus H101 on esophageal squamous cell carcinoma in vitro and in vivo

Replication-selective oncolytic virotherapy provides a novel modality to treat cancer by inducing cell death in tumor cells but not in normal cells. However, the utilization of oncolytic viruses as a stand-alone treatment is problematic due to their poor transduction efficiency in vivo. H101 was the first oncolytic adenovirus (Ads) to be approved by the Chinese FDA, and exhibits modest antitumor effects when applied as a single agent. The multiple histone deacetylase inhibitor trichostatin A (TSA) has been demonstrated to potently enhance the spread and replication of oncolytic Ads in several infection-resistant types of cancer. The present study aimed to investigate the antitumor effects of H101 in combination with TSA on esophageal squamous cell carcinoma (ESCC) in vitro and in vivo, and determine the mechanisms underlying these effects. H101 and TSA in combination increased the survival of mice harboring human ESCC cell line-tumor xenografts, as compared with mice treated with these agents individually. Therefore, TSA may enhance the antitumor effects of H101 in ESCC.

Overexpression of A613T and G462T variants of DNA polymerase β weakens chemotherapy sensitivity in esophageal cancer cell lines

BACKGROUND

Human DNA polymerase β (polβ) is a small monomeric protein that is essential for short-patch base excision repair. It plays an important role in regulating the sensitivity of tumor cells to chemotherapy.

METHODS

We evaluated the mutation of polβ in a larger cohort of esophageal cancer (EC) patients by RT-PCR and sequencing analysis. The function of the mutation was evaluated by CCK-8, in vivo tumor growth, and flow cytometry assays.

RESULTS

There are 229 patients with the polβ mutation, 18 patients with A613T mutation, 12 patients with G462T mutation among 538 ECs. Analysis results of survival time showed that EC patients with A613T, G462T mutation had a shorter survival than the others (P < 0.05). CCK-8 and flow cytometry assays results showed the A613T, G462T EC9706 cells were less sensitive than WT cells to 5-FU and cisplatin (P < 0.05). Experiments results in vivo showed that the tumor sizes of A613T and G462T group were larger than WT and polβ^-/- groups (P < 0.05).

CONCLUSIONS

In this study, we discovered A to T point mutation at nucleotide 613 (A613T) and G to T point mutation at nucleotide 462 (G462T) in the polβ gene through 538 EC patients cohort study. A613T and G462T variant of DNA polymerase β weaken chemotherapy sensitivity of esophageal cancer.

Dendritic cells loading autologous tumor lysate promote tumor angiogenesis

Dendritic cells (DC) have been exploited for vaccination against cancer for years. DC loading autologous tumor lysate (ATL-DC) have been assessed in ongoing clinical trials, but frequently do not meet expectation. In this study, we found that mice immunized with ATL-DC induced less protective anti-tumor effect than immunized with DC alone. The percentage of CD8+ T cells and the lysis efficiency of CTLs to auto tumor cells in ATL-DC vaccination group was less than that of DC group. Moreover, vaccination of mice with ATL-DC also promoted tumor angiogenesis by analyzing the CD31 positive microvessel density and hemoglobin content of tumor specimens. Human umbilical vein endothelial cells (HUVEC) have been proved effective in the anti-angiogenesis immunity against cancer. However, in the following research we found that the anti-tumor effect was attenuated while immunized mice with HUVEC combined with ATL-DC (HUVEC + ATL-DC). Furthermore, immunized mice with HUVEC + ATL-DC profoundly increased the tumor angiogenesis by analyzing the microvessel density and hemoglobin content of tumor specimens. These data suggest that vaccination using ATL-DC antagonized HUVEC induced anti-angiogenesis effect. Our research for the first time indicated that ATL-DC have the potential to promote the process of tumor angiogenesis in vivo. As vaccines based on DC loading autologous tumor lysate have been used in clinical, this find warned that the safety of this kind of vaccine should be taken into consideration seriously.

α-Solanine Modulates the Radiosensitivity of Esophageal Cancer Cells by Inducing MicroRNA 138 Expression

BACKGROUND

Esophageal cancer (EC) is one of the most common malignant tumors in the world. Due to difficulties with performing the operation, most patients choose to have palliative treatment instead. Radiotherapy is one of the main palliative treatments of EC. However, the clinical efficacy of radiotherapy is not satisfactory α-Solanine is a bioactive component of steroidal glycoalkaloids which has been demonstrated to exhibit anti-metastasis activity in different cancers. In the present study, we determined the effect of α-solanine on the radiosensitivity of EC cells and priliminarily explored the underlying molecular mechanisms.

METHODS

Cell Counting Kit-8 (CCK-8) assay was conducted to found the cytotoxic effect of α-solanine on EC cells. CCK-8 assay and colony-forming survival assays were performed to explore the effect of α-solanine on cell viability and proliferation of EC cells after irradiation. Immunofluorescence and comet assays were used to detect the effect of α-solanine on DNA repair capacity of EC cells after irradiation. The flow cytometry (FCM) and Hoechst/PI staining were conductd to study the effect of α-solanine on apoptosis of EC cells after irradiation.

RESULTS

The cytotoxic effect of α-solanine to EC cells was dose-dependent. The results of CCK-8, colony-forming survival assay, immunofluorescence, comet assay, FCM and Hoechst/PI staining showed that α-solanine could enhance the radiosensitivity of EC cells. α-Solanine could downregulate Survivin expression level by upregulating miR-138 expression in EC cells. Upregulation of miR-138 and knock down Survivin both enhanced the radiosensitivity of EC cells. Moreover, Survivin could restore the effect of α-solanine and miR-138 on radiosensitivity of EC cells.

CONCLUSIONS

α-solanine could enhance the radiosensitivity of esophageal cancer cells by inducing microRNA-138 expression, and probably be an effective radiosensitizer in treating EC.

Aloe-emodin suppresses esophageal cancer cell TE1 proliferation by inhibiting AKT and ERK phosphorylation

Aberrant AKT and extracellular signal-regulated kinase (ERK) activation is often observed in various human cancers. Both AKT and ERK are important in the phosphoinositide 3-kinase/AKT and mitogen-activated protein kinase kinase/ERK signaling pathways, which play vital roles in cell proliferation, differentiation and survival. Compounds that are able to block these pathways have therefore a promising use in cancer treatment and prevention. The present study revealed that AKT and ERK are activated in esophageal cancer TE1 cells. Aloe-emodin, an anthraquinone present in aloe latex, can suppress TE1 cell proliferation and anchor-independent cell growth. Aloe-emodin can also reduce the number of TE1 cells in S phase. Protein analysis indicated that aloe-emodin inhibits the phosphorylation of AKT and ERK in a dose-dependent manner. Overall, the present data indicate that aloe-emodin can suppress TE1 cell growth by inhibiting AKT and ERK phosphorylation, and suggest its clinical use for cancer therapy.