Search

The authors have requested that this preprint be removed from Research Square.

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.

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.

Understanding the molecular mechanisms of precancerous lesion of esophageal cancer is beneficial for early diagnosis and early treatment. The deletion of p53 gene is common in esophageal cancer, but its pathogenesis is still unclear. An animal model is urgently needed to study the mechanisms of esophageal cancer and p53 deficiency. KO mice (p53flox/flox.ED-L2-Cre+/−) and the corresponding control Loxp mice (p53flox/flox.ED-L2-Cre−/−) were obtained by crossing between the p53flox/flox mice and ED-L2-Cre+/− mice. Methylbenzylnitrosamine (NMBA) was injected subcutaneously to induce esophageal precancerous lesion of these two groups of mice. Hematoxylin and eosin staining analysis was performed to evaluate the number and extent of esophageal precancerous lesions in KO mice and Loxp mice at the 16th and 48th weeks. Immunohistochemistry analysis was used to detect the change of Ki67, P21, Bcl-2, and Bax proteins. The number and extent of esophageal precancerous lesions in KO mice were significantly increased compared with the control at the 16th and 48th weeks under the induction of NMBA. The Ki67, P21, Bcl-2, and Bax proteins also had cancer-related pathological characteristics. These results suggest that the esophageal precancerous lesion model was established under the combined effect of p53 gene deletion in esophageal epithelium and NMBA, which could provide a new esophageal precancerous lesion model to explore the mechanism of precancerous lesions.

Statins comprise a class of prescription drugs used for reducing cholesterol. Evidence has also showed that statins could reduce cancer incidence. However, the anti-tumor mechanism of statins has not been fully defined. Here, we found that atorvastatin inhibited proliferation of esophageal squamous cell carcinoma (ESCC) cells. The underlying mechanisms were explored by mass spectrometry. The proteome data revealed that atorvastatin inhibited the cAMP and Rap1 signal pathways, except for Ras signal pathway. Interestingly, phosphoproteome profiles suggested that ERKT185/Y187, CDK1T14, and BRAC1S1189 phosphorylation-mediated Th17 cell differentiation, Gap junction and the Platinum drug resistance pathway were down-regulated after atorvastatin treatment. The phosphorylation levels of ERKT185/Y187, CDK1T14 and BRAC1S1189 were confirmed by western blotting in KYSE150 cells. More importantly, atorvastatin suppresses ESCC tumor growth in PDX models. The molecular changes in tumor tissues were confirmed by immunohistochemistry. In conclusion, deep-proteome and phosphoproteome analysis reveal a comprehensive mechanism that contributes to atorvastatin's anti-tumor effect.

Esophageal squamous cell carcinoma (ESCC) is one of the leading causes of cancer death worldwide. It is urgent to develop new drugs to improve the prognosis of ESCC patients. Here, we found benzydamine, a locally acting non-steroidal anti-inflammatory drug, had potent cytotoxic effect on ESCC cells. Benzydamine could suppress ESCC proliferation in vivo and in vitro. In terms of mechanism, CDK2 was identified as a target of benzydamine by molecular docking, pull-down assay and in vitro kinase assay. Specifically, benzydamine inhibited the growth of ESCC cells by inhibiting CDK2 activity and affecting downstream phosphorylation of MCM2, c-Myc and Rb, resulting in cell cycle arrest. Our study illustrates that benzydamine inhibits the growth of ESCC cells by downregulating the CDK2 pathway.

Esophageal cancer is the ninth most common cancer and the sixth most common cause of cancer-related death worldwide, and the esophageal squamous cell carcinoma (ESCC) subtype accounts for about 90% of all cases of esophageal cancer globally. Currently, ESCC is usually diagnosed in late stages, and targeted therapy is lacking. Therefore, the development of ESCC-specific recognition molecules for an early detection and targeted treatment of ESCC is urgently needed. Aptamers are an excellent molecular recognition tool with unique advantages. In this manuscript, three aptamers (S2, S3, and S8) specific to ESCC cells were successfully screened via cell-SELEX. The experimental results displayed the high affinities of the three aptamers for target KYSE150 cells with dissociation constants in the nanomolar range. The specificity evaluation showed that S2 only bound target KYSE150 cells, but S3 and S8 were capable of targeting a series of ESCC cells. Moreover, several truncated aptamers were generated through sequence optimization. In particular, an ultrashort aptamer S3-2-3 with only 18 bases was successfully obtained; after labeling with Cy5 dyes, it was feasible for the specific imaging of ESCC tissues. Furthermore, the target types of the selected aptamers were preliminarily identified as membrane proteins, and target proteins could be captured by S3-2-3, which may be useful for biomarker discovery. Therefore, the selected aptamers hold great potential for clinical diagnosis, biomarker discovery, and the targeted therapy of ESCC.

Background: Esophageal squamous cell carcinoma (ESCC) is among one of the leading causes of cancer death worldwide owing to late detection and low survival rate. The clinical outcome of ESCC remains dismal. To date, the disease lacks available targeted therapies. Recently, drugs approved by the Food and Drug Administration have been reported to have potential as cancer chemoprevention agents. Methods: Benzydamine, available as a hydrochloride salt, a locally acting non-steroidal anti-inflammatory drug, was screened out among FDA-approved drugs owing to its effective cytotoxic effect on KYSE450 cells, which remained unexplored. Mass spectrometry, kinase prediction and Swiss Target Prediction were used to verify the potential target(s) of benzydamine. Patient-derived oesophageal xenograft mouse model were used to investigate the effect of benzydamine on tumor growth in vivo.Results: We found that benzydamine inhibited anchorage-dependent and -independent growth of ESCC cells. Kyoto Encyclopedia of Genes and Genomes pathway enrichment revealed that benzydamine attenuated five signaling pathways, including the DNA replication pathway. We further found that benzydamine could bind to CDK2 in its ATP-binding site. Inhibition of the activity of CDK2 suppressed the growth of ESCC cells and led to a G1/S cell cycle arrest. Additionally, knocking-down CDK2 decreased the sensitivity of ESCC cells to benzydamine hydrochloride. Notably, benzydamine suppressed tumour growth in a patient-derived oesophageal xenograft mouse model of ESCC in vivo.Conclusions: We have identified CDK2 as a potential target of benzydamine for the treatment and prevention of ESCC. Benzydamine suppressed the growth of ESCC cells by inhibiting the activity of CDK2.

Background: Colony-stimulating factor-1 (CSF1) is a cytokine that is closely related to normal organ growth and development as well as tumor progression. Objective: We aimed to summarize and clarify the reasons for the abnormal expression of CSF1 in tumors and explore the role of CSF1 in tumor progression. Furthermore, drug response analysis could provide a reference for clinical medication. Methods: The expression of CSF1 was analyzed by TCGA and CCLE. Besides, cBioPortal and MethSurv databases were used to conduct mutation and DNA methylation analyses. Further, correlations between CSF1 expression and tumor stage, survival, immune infiltration, drug sensitivity and enrichment analyses were validated via UALCAN, Kaplan-Meier plotter, TIMER, CTRP and Coexperia databases. Results: CSF1 is expressed in a variety of tissues; meaningfully, it can be detected in the blood. Compared with normal tissues, CSF1 expression was significantly decreased in most tumors. The missense mutation and DNA methylation of CSF1 might cause the downregulated expression. Moreover, decreased CSF1 expression was related to higher tumor stage and worse survival. Further, the promoter DNA methylation level of CSF1 was prognostically significant in most tumors. Besides, CSF1 was closely related to immune infiltration, especially macrophages. Importantly, CSF1 expression was associated with a good response to VEGFRs inhibitors, which may be due to the possible involvement of CSF1 in tumor angiogenesis and metastasis processes. Conclusion: The abnormal expression of CSF1 could serve as a promising biomarker of tumor progression and prognosis in pan-cancer. Significantly, angiogenesis and metastasis inhibitors may show a good response to CSF1-related tumors.

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.

Background Esophageal squamous cell carcinoma (ESCC) is a deadly disease with the poor prognosis in the world. The distal metastasis is the most death reason of ESCC. It is needed to have a comprehensive understanding of the molecular mechanism of metastasis to increase the free survive rate. T-LAK cell-originated protein kinase (TOPK) which is a MAPKK-like kinase takes an vital role in many physical and pathophysiological progress. However, the function of TOPK in ESCC metastasis was unclear. Methods Tissue array was used to evaluate the relationship between TOPK and ESCC patient with lymph node metastasis. Wound healing assay, transwell assay and lung metastasis mice model were assessed for the role of TOPK in the migration of ESCC cells in vitro and in vivo respectively. Protein kinase array, MS and molecular modeling were carried out to find the relational pathways and target protein of TOPK. Even, immune-fluorescence and western blot were performed to evaluate the mechanism of TOPK. Results We found that the high level of TOPK was correlated with the aggressive phenotype in ESCC tissues. Knocking down TOPK inhibited the invasion and migration of ESCC cells. We also verified that TOPK inhibitor HI-TOPK-032 inhibited the lung metastasis in ESCC cell exnograft model. Even more, molecular investigation indicated that TOPK promoted the invasion of ESCC cells by activing Src/GSK3β/STAT3, ERK pathway by binding with γ-catenin. Conclusion These findings reveal that TOPK was sincerely related with ESCC cell metastasis and TOPK promoted the invasion of ESCC cells by activing Src/GSK3β/STAT3, ERK pathway. This means that TOPK may be a potential molecular target for ESCC in clinic.

Understanding the molecular mechanisms of precancerous lesion of esophageal cancer is beneficial for early diagnosis and early treatment. The deletion of p53 gene is common in esophageal cancer, but its pathogenesis is still unclear. An animal model is urgently needed to study the mechanisms of esophageal cancer and p53 deficiency. KO mice (p53flox/flox.ED-L2-Cre+/−) and the corresponding control Loxp mice (p53flox/flox.ED-L2-Cre−/−) were obtained by crossing between the p53flox/flox mice and ED-L2-Cre+/− mice. Methylbenzylnitrosamine (NMBA) was injected subcutaneously to induce esophageal precancerous lesion of these two groups of mice. Hematoxylin and eosin staining analysis was performed to evaluate the number and extent of esophageal precancerous lesions in KO mice and Loxp mice at the 16th and 48th weeks. Immunohistochemistry analysis was used to detect the change of Ki67, P21, Bcl-2, and Bax proteins. The number and extent of esophageal precancerous lesions in KO mice were significantly increased compared with the control at the 16th and 48th weeks under the induction of NMBA. The Ki67, P21, Bcl-2, and Bax proteins also had cancer-related pathological characteristics. These results suggest that the esophageal precancerous lesion model was established under the combined effect of p53 gene deletion in esophageal epithelium and NMBA, which could provide a new esophageal precancerous lesion model to explore the mechanism of precancerous lesions.

Background Esophageal squamous cell carcinoma (ESCC) is a fatal disease with poor prognosis. The predominant reason for ESCC-related death is distal metastasis. A comprehensive understanding of the molecular mechanism underlying metastasis is needed for improving patient prognosis. T-LAK cell-originated protein kinase (TOPK) is a MAPKK-like kinase, which plays a vital role in various physiological and pathophysiological processes. However, the role of TOPK in ESCC metastasis is unclear. Methods Tissue array was used to evaluate the correlation between TOPK expression and ESCC lymph node metastasis. Wound healing assay, transwell assay, and lung metastasis mice model were used to examine the role of TOPK in the migration of ESCC cells in vitro and in vivo. Protein kinase array, mass spectrometry (MS), and molecular modeling were used to examine the pathways and direct target proteins of TOPK that are involved in ESCC metastasis. Additionally, immunofluorescence and western blotting analyses were performed to verify these findings. Results The enhanced expression of TOPK was correlated with lymph node metastasis in the ESCC tissues. TOPK knockdown or treatment with the TOPK inhibitor (HI-TOPK-032) decreased the invasion and migration of ESCC cells in vitro. HI-TOPK-032 also inhibited the lung metastasis in ESCC cell xenograft in vivo model. Moreover, TOPK promoted the invasion of ESCC cells by activating the Src/GSK3β/STAT3 and ERK signaling pathways via γ-catenin. Conclusion The findings of this study reveal that TOPK is involved in ESCC metastasis and promoted the ESCC cell mobility by activating the Src/GSK3β/STAT3 and ERK signaling pathways. This indicated that TOPK may be a potential molecular therapeutic target for ESCC metastasis.

Jie du tong ye san (JDTYS), a traditional Chinese herbal formula, has been used for cancer adjuvant therapy in clinical use and has been shown to be effective in cancer patients. However, the mechanism of JDTYS is still unclear. Therefore, the aim of the present study is to investigate the chemopreventive effects of JDTYS for esophageal squamous cell carcinoma (ESCC) and to clarify the potential mechanism. N-nitrosomethylbenzylamine (NMBA)-induced rat esophageal carcinogenesis was used to evaluate the effect of JDTYSin vivo. Rats were treated with NMBA 3 times per week, for a total of 5 weeks. Rats in the treated groups were given JDTYS for 35 weeks. When rats were euthanized, esophageal tissue and blood were collected to evaluate the effects of JDTYS. The pathological grading of the rat esophageal preneoplastic lesions was classified and statistically analyzed. The protein levels of c-Jun and Ki67 were determined by immunohistochemistry. In addition, inflammation markers nuclear factor kappa B (NF-κB), cyclooxygenase-2 (COX-2), and the cluster of differentiation molecule 11B (CD11B) were also determined by immunohistochemistry. Moreover, the expression of COX-2 and Pentraxin 3 (PTX3) in rat serum was determined by enzyme-linked immunosorbent assay (ELISA). JDTYS could inhibit the formation of NMBA-induced esophageal preneoplastic lesions. JDTYS could downregulate the expression of proliferation related proteins Ki67 and c-Jun. Moreover, inflammation related proteins NF-κB, COX-2, and CD11B were inhibited and PTX3 was increased by JDTYS. In all, JDTYS is a promising chemopreventive formula against esophageal carcinogenesis by regulating inflammation and inhibiting cell proliferation.

Angiogenesis is essential for the development, growth, and metastasis of solid tumors. Vaccination with viable human umbilical vein endothelial cells (HUVECs) has been used for antitumor angiogenesis. However, the limited immune response induced by HUVECs hinders their clinical application. In the present study, we found that HUVECs induced by a tumor microenvironment using the supernatant of murine CT26 colorectal cancer cells exerted a better antiangiogenic effect than HUVECs themselves. The inhibitory effect on tumor growth in the induced HUVEC group was significantly better than that of the HUVEC group, and the induced HUVEC group showed a strong inhibition in CD31-positive microvessel density in the tumor tissues. Moreover, the level of anti-induced HUVEC membrane protein antibody in mouse serum was profoundly higher in the induced HUVEC group than in the HUVEC group. Based on this, the antitumor effect of a vaccine with a combination of induced HUVECs and dendritic cell-loading CT26 antigen (DC-CT26) was evaluated. Notably, the microvessel density of tumor specimens was significantly lower in the combined vaccine group than in the control groups. Furthermore, the spleen index, the killing effect of cytotoxic T lymphocytes (CTLs), and the concentration of interferon-&gamma, in the serum were enhanced in the combined vaccine group. Based on these results, the combined vaccine targeting both tumor angiogenesis and tumor cells may be an attractive and effective cancer immunotherapy strategy.

Background: Esophageal squamous cell carcinoma (ESCC) still has high rates of incidence and mortality, despite developments in medical technology. Therefore, looking for cancer treatment drugs with high efficiency and low toxicity remains very important. In the previous study, we screened FDA-approved drugs, approved for uses other than tumor treatment, and found that mefloquine (MQ), which is used for prevention and treatment of malaria, inhibited clone formation of ESCC cells. Methods: Proteomics and mass spectrometry (MS) were applied to profile proteome changes in ESCC cells after MQ treatment. KEGG was performed to analyse the significantly down-regulated pathways and proteins. Electron microscopy was used to observe mitochondrial changes in MQ-treated KYSE150 cells. And patient derived xenograft (PDX) mouse model was used to observe the anti-tumor effect of MQ in vivo. Findings: MS analyse showed that various proteins changed in MQ-treated KYSE150 cells. KEGG analyse identified dysregulated pathways and proteins. Among these proteins, SDHC, SDHD, MTCO3 and NDUFV3, all known to be essential enzymes in the mitochondrial respiration chain, were involved in these pathways and were notably down-regulated in MQ-treated cells. Meanwhile, mitochondrial autophagy was verified in MQ-treated cells by electron microscopy. Furthermore, MQ significantly inhibited tumor growth in a patient-derived xenograft mouse model of ESCC. All considered, MQ suppressed ESCC cell proliferation by induction of mitochondrial autophagy. Interpretation: Our data suggested that MQ may be a promising drug for ESCC treatment and chemoprevention. Funding Statement: This work was supported by grants from the National Natural Science Foundations of China (No. 81872335, 81572812, and 81472324) and the Natural Science Foundations of Henan (No. 161100510300). Declaration of Interests: The authors declare no conflicts of interest. Ethics Approval Statement: All procedures involving animals in this study were approved by the Animal Ethics Committee.

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.

A large volume of data indicates that controlling tumor-associated angiogenesis is a promising therapy against cancer. However, angiogenesis is a complex process, little is known about the differential gene expression in the process of normal endothelial cell differentiation toward tumor vascular endothelial cells induced by tumor microenvironment. The aim of this study is to investigate the effect of tumor microenvironment simulated by the supernatant of esophageal squamous cancer cells (KYSE70) on normal endothelial cells (HUVECs) at the whole genome level. The gene expression profile was studied through gene ontology and signal pathway analysis. Compared with the normal HUVECs, a total of 3769 differentially expressed genes in induced HUVECs were detected, including 1609 upregulated genes and 2160 downregulated genes. Moreover, the microarray data analysis showed that 11 significant biological processes and 10 significant signaling pathways changed most, which are associated with angiogenesis and cell differentiation. According to the different expression levels in the microarrays and their functions, four differentially expressed genes involved in tumor angiogenesis and cell differentiation (IL6, VEGFA, S1PR1, TYMP) were selected and analyzed by qRT-PCR. The qRT-PCR results were consistent with the microarray data. Furthermore, we simulated the tumor microenvironment by human esophageal carcinoma tissue homogenate to investigate its effect on HUVECs, the qRT-PCR results indicated that the above genes were highly expressed in HUVECs after induction by esophageal carcinoma tissue homogenate. In conclusion, tumor microenvironment impact on normal endothelial cells differentiated toward tumor vascular endothelial cells, and the selected genes, which are associated with tumor angiogenesis, would be anti-angiogenesis targets against esophageal carcinoma.

Esophageal squamous cell carcinoma (ESCC) is the predominant histological type of esophageal carcinoma in China. The overall 5-year survival rate of ESCC patients is in the low range of 15-25%. One important reason for the poor prognosis is that the underlying molecular mechanisms are unclear. Furthermore, the development of effective therapeutic strategies to improve patient outcome is needed. Animal models can be beneficial to analyze the molecular mechanisms as well as specific clinical therapeutic strategies for esophageal cancer. In recent years, patient-derived xenografts (PDXs) have been widely used in numerous types of cancers to investigate the basic mechanisms and to conduct preclinical research. Accumulating evidence indicates that the PDX model is an important tool for basic and clinical research. Herein, we successfully established 14 ESCC PDXs. These PDX models preserved the patient pathological characteristics and effectively reflected the patient biological heterogeneity. Cancers exhibit diverse growth rates and tumor texture, even more, they have different signaling pathways. The PDX model is a superior strategy for understanding the underlying molecular mechanisms of ESCC and for screening new therapeutic strategies for ESCC patients.

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.

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.

As millions of people are diagnosed with diabetes every year in China, many diabetes-related websites in Chinese provide news and articles. However, most of the online articles are uncategorized or lack a clear or unified topic, users often cannot find their topics of interest effectively and efficiently. The problem of health text classification on Chinese websites cannot be easily addressed by applying existing approaches, which have been used for English documents, in a straightforward manner. To address this problem and meet users’ demand for diabetes-related information needs, we propose a Chinese domain lexicon, adopt some professional diabetes topic explanations as domain knowledge and incorporate them into deep learning approach to form our topic classification framework. Our experiments using real datasets showed that the framework significantly achieved a higher effectiveness and accuracy in categorizing diabetes-related topics than most of the state-of-the-art benchmark approaches. Our experimental analysis also revealed that some health websites provided some incorrect or misleading category information.

// Yi Yang 1, 2, 3 , Guoguo Jin 1, 2 , Hangfan Liu 1, 2 , Kangdong Liu 1, 2 , Jimin Zhao 1, 2 , Xinhuan Chen 1, 2 , Dongyu Wang 1, 2 , Ruihua Bai 4 , Xiang Li 1, 2 , Yanan Jang 1, 2 , Jing Lu 1, 2 , Ying Xing 1, 3 and Ziming Dong 1, 2 1 Department of Pathophysiology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China 2 Collaborative Innovation Center of Henan Province for Cancer Chemoprevention, Zhengzhou, Henan 450001, P.R. China 3 Department of Physiology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China 4 Department of Pathology, Henan Cancer Hospital, Zhengzhou University, Zhengzhou, Henan 450008, P.R. China Correspondence to: Jing Lu, email: lujing@zzu.edu.cn Ying Xing, email: xingy@zzu.edu.cn Ziming Dong, email: dongzm@zzu.edu.cn Keywords: metformin, angiogenesis, ESCC, microenvironment, TECs Received: January 23, 2017 Accepted: July 18, 2017 Published: August 18, 2017 ABSTRACT 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.

Hydroacylation reactions and aza-benzoin reactions have attracted considerable attention from experimental chemists. Recently, Wang et al. reported an interesting reaction of N-heterocyclic carbene (NHC)-catalyzed addition of aldehyde to enamide, in which both hydroacylation and aza-benzoin reactions may be involved. Thus, understanding the competing relationship between them is of great interest. Now, density functional theory (DFT) investigation was performed to elucidate this issue. Our results reveal that enamide can tautomerize to its imine isomer with the assistance of HCO3−. The addition of NHC to aldehydes formed Breslow intermediate, which can go through cross-coupling with enamide via hydroacylation reaction or its imine isomer via aza-benzoin reaction. The aza-benzoin reaction requires relatively lower free energy barrier than the hydroacylation reaction. The more polar characteristic of C=N group in the imine isomers, and the more advantageous stereoelectronic effect in the carbon-carbon bond forming transition states in aza-benzoin pathway were identified to determine that the imine isomer can react with the Breslow intermediate more easily. Furthermore, the origin of enantioselectivities for the reaction was explored and reasonably explained by structural analyses on key transition states. The work should provide valuable insights for rational design of switchable NHC-catalyzed hydroacylation and aza-benzoin reactions with high stereoselectivity.

Weibo Chinese microblog has become a popular social media platform for users to share health-related information. However, illegitimate users or spammers often generate and spread false or misleading health information so as to advertise and attract more attention. To address this issue, we propose a health-related spammer detection approach on Chinese social media. Our approach is a deep belief network DBN based model incorporating a comprehensive feature set, including burstiness-based features, profile-based features, and content-based features, to identify spammers who spread misleading health-related information. Especially, we create a medical and health domain lexicon to better extract content-based features. The experimental results show the approach achieves an F1 score of 86i¾?% in detecting spammer and significantly outperforms the benchmark methods using baseline features.

As millions of people are diagnosed with diabetes every year, the demand for information about diabetes continues to increase. China is one of the countries with a large population of diabetes patients. Many Chinese health websites provide diabetes related news and articles. However, because most of the online articles are uncategorized or lack a clear topic and theme, users often cannot find their topics of interest effectively and efficiently. The problem of health topic identification and categorization on Chinese websites cannot be easily addressed by applying existing approaches and methods, which have been used for English documents, in a straightforward manner. To address this problem and meet users’ demand for diabetes related information needs, we propose a deep learning based framework to identify and categorize topics related to diabetes in online Chinese articles. Our experiments using datasets with over 19,000 online articles showed that the framework achieved a higher effectiveness and accuracy in categorizing diabetes related topics than most of the state-of-the-art benchmark approaches.

Chronic hepatitis B virus (HBV) infection is a key factor for hepatocellular carcinoma worldwide. Ribonucleotide reductase (RR) regulates the deoxyribonucleoside triphosphates biosynthesis and serves as a target for anti-cancer therapy. Here, we demonstrate that RR is essential for HBV replication and the viral covalently-closed-circular DNA (cccDNA) synthesis in host liver cells. By performing computer-assisted virtual screening against the crystal structure of RR small subunit M2 (RRM2), osalmid, was identified as a potential RRM2-targeting compound. Osalmid was shown to be 10-fold more active in inhibiting RR activity than hydroxyurea, and significantly inhibited HBV DNA and cccDNA synthesis in HepG2.2.15 cells. In contrast, hydroxyurea and the RR large subunit (RRM1)-inhibitory drug gemcitabine showed little selective activity against HBV replication. In addition, osalmid also was shown to possess potent activity against a 3TC-resistant HBV strain, suggesting utility in treating drug-resistant HBV infections. Interestingly, osalmid showed synergistic effects with lamivudine (3TC) in vitro and in vivo without significant toxicity, and was shown to inhibit RR activity in vivo, thus verifying its in vivo function. Furthermore, 4-cyclopropyl-2-fluoro-N-(4-hydroxyphenyl) benzamide (YZ51), a novel derivative of osalmid, showed higher efficacy than osalmid with more potent RR inhibitory activity. These results suggest that RRM2 might be targeted for HBV inhibition, and the RRM2-targeting compound osalmid and its derivative YZ51 could be a novel class of anti-HBV candidates with potential use for hepatitis B and HBV-related HCC treatment.

In the present work, the upper limit of x in Ba 6−3 x Nd 8+2 x Ti 18 O 54 ceramics was determined by investigating the phase constitution as the function of composition and process conditions. For the compositions of x ≤ 0.75, the new tungsten bronze structure is stable and the single phase structure is easy to be obtained. While, the new tungsten bronze structure becomes unstable for compositions of x = 0.8, 0.9 and 1.0, where the new tungsten bronze major phase is generally detected together with some secondary phases. The excellent microwave dielectric characteristics are not only obtained at x = 0.67 but also obtained at 0.8 and 0.9.

Tumor microenvironment has a crucial role in cancer development and progression, whereas the mechanism of how it regulates angiogenesis is unclear. In this study, we simulated the colorectal carcinoma microenvironment by conditioned medium (CM) of colorectal carcinoma cell lines (SW620, HT-29, HCT116) supernatant or colorectal carcinoma tissue homogenate supernatant to induce normal endothelial cells (NECs). We found that colorectal carcinoma CM promoted tumor angiogenesis by coercing NECs toward tumor endothelial cells (TECs) with the activation of the JAK/STAT3 signaling pathway. Antibody array analysis showed HT-29 supernatant contained numerous angiogenesis-related proteins, especially IL-8. Interestingly, the production of IL-8 in NECs induced by HT-29 CM was also increased. We also verified the crucial role of IL-8 in promoting the CM-induced angiogenesis, as IL-8 repression by neutralizing antibody abolished the transition of NECs toward TECs. Curcumin and (−)-epigallocatechin-3-gallate (EGCG) are broadly investigated in cancer chemoprevention. However, poor bioavailability hurdles their application alone, and the mechanism of their anti-angiogenesis still need to be illuminated. Here, we found that curcumin combination with EGCG attenuated the tumor CM-induced transition of NECs toward TECs by inhibiting JAK/STAT3 signaling pathway. Furthermore, the combination of curcumin and EGCG markedly reduced tumor growth and angiogenesis in the colorectal carcinoma PDX mouse model, and the combined anti-angiogenic effect was better than that of curcumin or EGCG alone. Taken together, our findings provide a new mechanism of tumor angiogenesis, and the combination of curcumin and EGCG represents a potential anti-angiogenic therapeutic method for colorectal carcinoma.

The proliferation of texts in Web presents great challenges on knowledge discovery in text collections. Clustering provides us with a powerful tool to organize the information and recognize the structure of the information. Most text clustering techniques are designed to deal with either long or short texts. However many real-life collections are often made up of both long and short texts, namely mixed length texts. The current text clustering techniques are unsatisfactory, for they don’t distinguish the sparseness and high dimension of the mixed length texts. In this paper, we propose a novel approach - Length-Aware Dual Latent Dirichlet Allocation (ADLDA), which is used for clustering the mixed length texts via obtaining auxiliary knowledge from long (short) texts for short (long) texts in the collections. The degree of mutual auxiliary is based on the ratio of long texts and short texts in a corpus. Experimental results on real datasets show our approach achieves superior performance over other state-of the-art text clustering approaches for mixed length texts.