Identification and validation of genes involved in gastric tumorigenesis

The biological functions and related signaling pathways of SPON2

Spondin-2 (SPON2), also referred to as M-spondin or DIL-1, is a member of the extracellular matrix protein family known as Mindin-F-spondin (FS). SPON2 can be used as a broad-spectrum tumor marker for more than a dozen tumors, mainly prostate cancer. Meanwhile, SPON2 is also a potential biomarker for the diagnosis of certain non-tumor diseases. Additionally, SPON2 plays a pivotal role in regulating tumor metastasis and progression. In normal tissues, SPON2 has a variety of biological functions represented by promoting growth and development and cell proliferation. This paper presents a comprehensive overview of the regulatory mechanisms, diagnostic potential as a broad-spectrum biomarker, diverse biological functions, involvement in various signaling pathways, and clinical applications of SPON2.

Aldo-keto Reductase 1B10 Restrains Cell Migration, Invasion, and Adhesion of Gastric Cancer via Regulating Integrin Subunit Alpha 5

BACKGROUND/AIMS

Gastric cancer is a prevalent malignancy with unfavorable prognosis partially resulting from its high metastasis rate. Clarifying the molecular mechanism of gastric cancer occurrence and progression for improvement of therapeutic efficacy and prognosis is needed. The study tended to delineate the role and regulatory mechanism of aldo-keto reductase 1B10 (AKR1B10) in gastric cancer progression.

MATERIALS AND METHODS

The relationship of AKR1B10 expression with survival rate in gastric cancer was analyzed through Kaplan-Meier analysis. The mRNA levels of AKR1B10 and integrin subunit alpha 5 (ITGA5) in gastric cancer tissues and cell lines were measured by real-time quantitative polymerase chain reaction. Protein levels of AKR1B10 and integrin subunit alpha 5 were assayed via western blot. The molecular relationship between AKR1B10 and ITGA5 was analyzed by co-immunoprecipitation assay. Cell viability was assayed through Cell Counting Kit-8, invasion and migration of tumor cells was assessed through wound healing and transwell assays. Transwell assay was utilized to detect invasion. The adhesion of gastric cancer cells was detected using cell adhesion assays.

RESULTS

The results unveiled that integrin subunit alpha 5 was upregulated, while AKR1B10 was downregulated in gastric cancer tissues and cells. Overexpressing AKR1B10 hindered gastric cancer cell proliferation, migration, invasion and adhesion. It was striking that we certified the inhibitory effect of AKR1B10 on integrin subunit alpha 5 expression and their (AKR1B10 and ITGA5)) negative relationship via bioinformatics method, real-time quantitative polymerase chain reaction, and co-immunoprecipitation assays. Via rescue experiments, it was concluded that AKR1B10 served as tumor suppressor potentially by ITGA5 expression in gastric cancer.

CONCLUSION

Our results indicated that AKR1B10 inhibited migration, invasion, and adhesion of gastric cancer cells via modulation of ITGA5.

Comprehensive analysis of the oncogenic and immunological role of SPON2 in human tumors

BACKGROUND

Sapiens spondin-2 (SPON2) is a protein found in the extracellular matrix that plays a role in a number of processes, including immune reactions and cell adhesion, and is closely linked to the emergence of a number of tumor types. However, we know very little about Sapiens spondin-2. Therefore, we performed a systematic pan-carcinogenic analysis to explore the relationship between Sapiens spondin-2 and cancers.

MATERIALS AND METHODS

By comprehensive use of datasets from TCGA, GEO, GTEx, HPA, CPTAC, GEPIA2, TIMER2, cBioPortal, STRING, we adopted bioinformatics methods to dig up the potential carcinogenesis of SPON2, including dissecting the correlation between SPON2 and gene expression, prognosis, gene mutation, Immunohistochemistry staining, immune cell infiltration, and constructed the interaction network of a total of 54 SPON2-binding proteins as well as explored the enrichment analysis of SPON2-related partners.

RESULTS

The expression of Sapiens spondin-2 in most tumor tissues was higher than that of normal tissues. In addition, SPON2 showed the early diagnostic value in 33 kinds of tumors and was positively or negatively associated with the prognosis of different tumors. It also validates that SPON2 is the gene associated with the majority of immune-infiltrating cells in pan-cancer. High SPON2 expression is associated with tumor progression related pathways.

CONCLUSION

We found and validated the potential use of SPON2 in cancer detection for the first time through pan-cancer analysis. The expression levels of SPON2 in various tumors were quite different from those in normal tissues. Furthermore, the performance of SPON2 in tumorigenesis and tumor immunity verified our hypothesis. At the same time, it has high specificity and sensitivity in cancer detection. Therefore, SPON2 can be employed as an auxiliary index for the initial diagnosis of tumors and a prognostic marker for various types of tumors.

Network and functional analyses of differentially expressed genes in gastric cancer provide new biomarkers associated with disease pathogenesis

BACKGROUND

Gastric cancer is a dominant source of cancer-related death around the globe and a serious threat to human health. However, there are very few practical diagnostic approaches and biomarkers for the treatment of this complex disease.

METHODS

This study aimed to evaluate the association between differentially expressed genes (DEGs), which may function as potential biomarkers, and the diagnosis and treatment of gastric cancer (GC). We constructed a protein-protein interaction network from DEGs followed by network clustering. Members of the two most extensive modules went under the enrichment analysis. We introduced a number of hub genes and gene families playing essential roles in oncogenic pathways and the pathogenesis of gastric cancer. Enriched terms for Biological Process were obtained from the "GO" repository.

RESULTS

A total of 307 DEGs were identified between GC and their corresponding normal adjacent tissue samples in GSE63089 datasets, including 261 upregulated and 261 downregulated genes. The top five hub genes in the PPI network were CDK1, CCNB1, CCNA2, CDC20, and PBK. They are involved in focal adhesion formation, extracellular matrix remodeling, cell migration, survival signals, and cell proliferation. No significant survival result was found for these hub genes.

CONCLUSIONS

Using comprehensive analysis and bioinformatics methods, important key pathways and pivotal genes related to GC progression were identified, potentially informing further studies and new therapeutic targets for GC treatment.

Retinal determination gene networks: from biological functions to therapeutic strategies

The retinal determinant gene network (RDGN), originally discovered as a critical determinator in Drosophila eye specification, has become an important regulatory network in tumorigenesis and progression, as well as organogenesis. This network is not only associated with malignant biological behaviors of tumors, such as proliferation, and invasion, but also regulates the development of multiple mammalian organs. Three members of this conservative network have been extensively investigated, including DACH, SIX, and EYA. Dysregulated RDGN signaling is associated with the initiation and progression of tumors. In recent years, it has been found that the members of this network can be used as prognostic markers for cancer patients. Moreover, they are considered to be potential therapeutic targets for cancer. Here, we summarize the research progress of RDGN members from biological functions to signaling transduction, especially emphasizing their effects on tumors. Additionally, we discuss the roles of RDGN members in the development of organs and tissue as well as their correlations with the pathogenesis of chronic kidney disease and coronary heart disease. By summarizing the roles of RDGN members in human diseases, we hope to promote future investigations into RDGN and provide potential therapeutic strategies for patients.

A Novel Prognostic Marker and Therapeutic Target Associated with Glioma Progression in a Tumor Immune Microenvironment

Background

Immune microenvironment serves a vital role in glioma progression, and a large number of studies have found that tumor progression can be reduced to some extent by modulating the immune process in tumors.

Materials and Methods

ImmuneScore of each sample in CGGA datasets were calculated with Estimate R package, and samples were grouped by median ImmuneScore values for differential analysis to obtain immune microenvironment differential genes. We further conducted survival analysis, ROC curve analysis, independent prognostic analysis, and clinical correlation analysis on glioma sample genes in CGGA to obtain glioma prognostic genes, and then identified their intersection with immune microenvironment DEGs by Venn tool. The GEPIA and UALCAN databases were used to verify the differential expression of intersecting genes in the glioma and normal brain and to identify our target gene. After validation of their prognostic value, we constructed a nomogram to calculate the risk score and to estimate the accuracy of prognostic model. We mined co-expression genes, enriched functions and pathways, and correlations to immune cell infiltration of unigene with an online database. Finally, we verified the differential expression of FCGBP in glioma by immunohistochemical staining.

Results

We finally selected Fc fragment of IgG-binding protein (FCGBP) as our study gene. The prognostic values of FCGBP were validated by a series of analyses. Immunohistochemical staining showed that FCGBP expression increased in gliomas and was up-regulated with the progression of glioma grade.

Conclusion

As a key unigene in glioma progression, FCGBP contributes to the regulation of immune microenvironment and has the potential to be a prognostic biomarker and immune targets.

The Role of CXC Chemokines in Cancer Progression

CXC chemokines are small chemotactic and secreted cytokines. Studies have shown that CXC chemokines are dysregulated in multiple types of cancer and are closely correlated with tumor progression. The CXC chemokine family has a dual function in tumor development, either tumor-promoting or tumor-suppressive depending on the context of cellular signaling. Recent evidence highlights the pro-tumorigenic properties of CXC chemokines in most human cancers. CXC chemokines were found to play pivotal roles in promoting angiogenesis, stimulating inflammatory responses, and facilitating tumor metastases. Enhanced expression of CXC chemokines is always signatured with inferior survival and prognosis. The levels of CXC chemokines in cancer patients are in dynamic change according to the tumor contexts (e.g., chemotherapy resistance and tumor recurrence after surgery). Thus, CXC chemokines have great potential to be used as diagnostic and prognostic biomarkers and therapeutic targets. Currently, the molecular mechanisms underlying the effect of CXC chemokines on tumor inflammation and metastasis remain unclear and application of antagonists and neutralizing antibodies of CXC chemokines signaling for cancer therapy is still not fully established. This article will review the roles of CXC chemokines in promoting tumorigenesis and progression and address the future research directions of CXC chemokines for cancer treatment.

PRSS2 remodels the tumor microenvironment via repression of Tsp1 to stimulate tumor growth and progression

The progression of cancer from localized to metastatic disease is the primary cause of morbidity and mortality. The interplay between the tumor and its microenvironment is the key driver in this process of tumor progression. In order for tumors to progress and metastasize they must reprogram the cells that make up the microenvironment to promote tumor growth and suppress endogenous defense systems, such as the immune and inflammatory response. We have previously demonstrated that stimulation of Tsp-1 in the tumor microenvironment (TME) potently inhibits tumor growth and progression. Here, we identify a novel tumor-mediated mechanism that represses the expression of Tsp-1 in the TME via secretion of the serine protease PRSS2. We demonstrate that PRSS2 represses Tsp-1, not via its enzymatic activity, but by binding to low-density lipoprotein receptor-related protein 1 (LRP1). These findings describe a hitherto undescribed activity for PRSS2 through binding to LRP1 and represent a potential therapeutic strategy to treat cancer by blocking the PRSS2-mediated repression of Tsp-1. Based on the ability of PRSS2 to reprogram the tumor microenvironment, this discovery could lead to the development of therapeutic agents that are indication agnostic.

Simulated Microgravity Influences Immunity-Related Biomarkers in Lung Cancer

Microgravity is a novel strategy that may serve as a complementary tool to develop future cancer therapies. In lung cancer, the influence of microgravity on cellular processes and the migratory capacity of cells is well addressed. However, its effect on the mechanisms that drive lung cancer progression remains in their infancy. In this study, 13 differentially expressed genes were shown to be associated with the prognosis of lung cancer under simulated microgravity (SMG). Using gene set enrichment analysis, these genes are enriched in humoral immunity pathways. In lieu, alveolar basal-epithelial (A549) cells were exposed to SMG via a 2D clinostat system in vitro. In addition to morphology change and decrease in proliferation rate, SMG reverted the epithelial-to-mesenchymal transition (EMT) phenotype of A549, a key mechanism in cancer progression. This was evidenced by increased epithelial E-cadherin expression and decreased mesenchymal N-cadherin expression, hence exhibiting a less metastatic state. Interestingly, we observed increased expression of FCGBP, BPIFB, F5, CST1, and CFB and their correlation to EMT under SMG, rendering them potential tumor suppressor biomarkers. Together, these findings reveal new opportunities to establish novel therapeutic strategies for lung cancer treatment.

Machine learning based identification of hub genes in renal clear cell carcinoma using multi-omics data

Renal cell carcinoma is one of the most universal urinary system cancers in the world. The most common renal cell carcinoma subtype is renal clear cell carcinoma. It is usually associated with high rates of metastasis and mortality. Therefore, finding effective therapeutic targets and prognostic molecular markers is of great significance to improve the early diagnosis rate and prognostic accuracy of renal clear cell carcinoma. In this work, we successfully identified six hub genes that are closely related to the occurrence, development and prognosis of renal clear cell carcinoma and proposed three new potential prognostic markers, namely ATP4B, AC144831.1 and Tfcp2l1 through differentially expressed genes (DEGs) analysis, GO functional enrichment and KEGG pathway analysis, WGCNA analysis, and survival analysis. In addition, we established machine learning models to predict the occurrence of tumors through the gene expression data of patients. It is expected that the results of this study can provide reference value for the treatment of renal clear cell carcinoma.

CXCL5: A coachman to drive cancer progression

Chemokines are a class of pro-inflammatory cytokines that can recruit and activate chemotactic cells. C‐X‐C motif chemokine ligand 5 (CXCL5) is a member of the chemokine family binding CXCR2 (C-X-C Motif Chemokine Receptor 2), a G-protein coupled receptor. Accumulated evidence has shown that dysregulated CXCL5 participates in tumor metastasis and angiogenesis in human malignant tumors. In this review, we summarized the advances in research on CXCL5, including its dysregulation in different tumors and the mechanism associated with tumor behavior (formation of the immunosuppressive microenvironment, promotion of tumor angiogenesis, and metastasis). We also summarized and discussed the perspective about the potential application of CXCL5 in tumor therapy targeting the tumor inflammatory microenvironment.

Role of the mucin-like glycoprotein FCGBP in mucosal immunity and cancer

IgGFc-binding protein (FCGBP) is a mucin first detected in the intestinal epithelium. It plays an important role in innate mucosal epithelial defense, tumor metastasis, and tumor immunity. FCGBP forms disulfide-linked heterodimers with mucin-2 and members of the trefoil factor family. These formed complexes inhibit bacterial attachment to mucosal surfaces, affect the motility of pathogens, and support their clearance. Altered FCGBP expression levels may be important in the pathologic processes of Crohn’s disease and ulcerative colitis. FCGBP is also involved in regulating the infiltration of immune cells into tumor microenvironments. Thus, the molecule is a valuable marker of tumor prognosis. This review summarizes the functional relevance and role of FCGBP in immune responses and disease development, and highlights the potential role in diagnosis and predicting tumor prognosis.

Identification and validation of plasma biomarkers for diagnosis of breast cancer in South Asian women

Breast cancer is the most common malignancy among women globally. Development of a reliable plasma biomarker panel might serve as a non-invasive and cost-effective means for population-based screening of the disease. Transcriptomic profiling of breast tumour, paired normal and apparently normal tissues, followed by validation of the shortlisted genes using TaqMan® Low density arrays and Quantitative real-time PCR was performed in South Asian women. Fifteen candidate protein markers and 3 candidate epigenetic markers were validated first in primary breast tumours and then in plasma samples of cases [N = 202 invasive, 16 DCIS] and controls [N = 203 healthy, 37 benign] using antibody array and methylation specific PCR. Diagnostic efficiency of single and combined markers was assessed. Combination of 6 protein markers (Adipsin, Leptin, Syndecan-1, Basic fibroblast growth factor, Interleukin 17B and Dickopff-3) resulted in 65% sensitivity and 80% specificity in detecting breast cancer. Multivariate diagnostic analysis of methylation status of SOSTDC1, DACT2, WIF1 showed 100% sensitivity and up to 91% specificity in discriminating BC from benign and controls. Hence, combination of SOSTDC1, DACT2 and WIF1 was effective in differentiating breast cancer [non-invasive and invasive] from benign diseases of the breast and healthy individuals and could help as a complementary diagnostic tool for breast cancer.

Uterine Sensitization-Associated Gene-1 in the Progression of Kidney Diseases

Uterine sensitization-associated gene-1 (USAG-1), originally identified as a secretory protein preferentially expressed in the sensitized rat endometrium, has been determined to modulate bone morphogenetic protein (BMP) and Wnt expression to play important roles in kidney disease. USAG-1 affects the progression of acute and chronic kidney damage and the recovery of allograft kidney function by regulating the BMP and Wnt signaling pathways. Moreover, USAG-1 has been found to be involved in the process of T cell immune response, and its ability to inhibit germinal center activity and reduce humoral immunity is of great significance for the treatment of autoimmune nephropathy and antibody-mediated rejection (AMR) after renal transplantation. This article summarizes the many advances made regarding the roles of USAG-1 in the progression of kidney disease and outlines potential treatments.

LINC01133 hampers the development of gastric cancer through increasing somatostatin via binding to microRNA-576-5p

Aim: Our study aimed at investigating how LINC01133 functions in gastric cancer (GC) progression. Materials & methods: Gain-of-function and loss-of-function approaches were applied to analyze the effects of LINC01133, microRNA-576-5p (miR-576-5p) and somatostatin (SST) on the biological behaviors of GC cells and in tumor-bearing nude mice. Results: GC tissues and cells showed low expression of LINC01133, and LINC01133 overexpression decreased malignant phenotypes of GC cells. Moreover, LINC01133 upregulated SST through binding to miR-576-5p. Overexpressing miR-576-5p or suppressing SST reversed the functions of LINC01133 in biological potentials of GC cells and tumor growth. Conclusion: LINC01133 overexpression may inhibit GC development by downregulation of miR-576-5p and upregulation of SST, which suggests new therapeutic targets for GC.

Identification of 5-methylcytosine-related signature for predicting prognosis in ovarian cancer

BACKGROUND

Ovarian cancer is one of the most common malignancies often resulting in a poor prognosis. 5-methylcytosine (m5C) is a common epigenetic modification with roles in eukaryotes. However, the expression and function of m5C regulatory factors in ovarian cancer remained unclear.

RESULTS

Two molecular subtypes with different prognostic and clinicopathological features were identified based on m5C regulatory factors. Meanwhile, functional annotation showed that in the two subtypes, 452 differentially expressed genes were significantly related to the malignant progression of ovarian cancer. Subsequently, four m5C genes were screened to construct a risk marker predictive of overall survival and indicative of clinicopathological features of ovarian cancer, also the robustness of the risk marker was verified in external dataset and internal validation set. multifactorial cox regression analysis and nomogram demonstrated that risk score was an independent prognostic factor for ovarian cancer prognosis.

CONCLUSION

In conclusion, our results revealed that m5C-related genes play a critical role in tumor progression in ovarian cancer. Further detection of m5C methylation could provide a novel targeted therapy for treating ovarian cancer.

CXCL5/CXCR2 axis in tumor microenvironment as potential diagnostic biomarker and therapeutic target

The components of the tumor microenvironment (TME) in solid tumors, especially chemokines, are currently attracting much attention from scientists. C-X-C motif chemokine ligand 5 (CXCL5) is one of the important chemokines in TME. Overexpression of CXCL5 is closely related to the survival time, recurrence and metastasis of cancer patients. In TME, CXCL5 binds to its receptors, such as C-X-C motif chemokine receptor 2 (CXCR2), to participate in the recruitment of immune cells and promote angiogenesis, tumor growth, and metastasis. The CXCL5/CXCR2 axis can act as a bridge between tumor cells and host cells in TME. Blocking the transmission of CXCL5/CXCR2 signals can increase the sensitivity and effectiveness of immunotherapy and slow down tumor progression. CXCL5 and CXCR2 are also regarded as biomarkers for predicting prognosis and molecular targets for customizing the treatment. In this review, we summarized the current literature regarding the biological functions and clinical significance of CXCL5/CXCR2 axis in TME. The possibility to use CXCL5 and CXCR2 as potential prognostic biomarkers and therapeutic targets in cancer is also discussed.

A bioinformatic analysis: the overexpression and clinical significance of FCGBP in ovarian cancer

Fc fragment of IgG-binding protein (FCGBP) is differentially expressed in various tumors. However, the correlation between FCGBP and immune cell infiltration in ovarian cancer remains unclear. FCGBP expression was analyzed using The Cancer Genome Atlas (TCGA) pan-cancer data, and the ovarian cancer expression profile was analyzed using the Gene Expression Omnibus database. The clinical prognostic value of FCGBP was evaluated using clinical survival data from TCGA. Enrichment analysis of FCGBP was performed using the R package clusterProfiler. Based on known immune cell infiltration scores for samples found in TCGA, we analyzed the association between immune cell infiltration level and FCGBP expression. FCGBP was highly expressed and associated with poorer overall survival (p = 0.00051) and disease-specific survival (p = 0.0012) in ovarian cancer and other tumors. Additionally, high FCGBP expression correlated significantly with immune-related gene sets, including those involved in chemokine signaling pathways and innate and adaptive immunity. Further analysis showed that M2 macrophage infiltration increased and M1 macrophage infiltration decreased in tissues with high FCGBP expression. Our study suggests that FCGBP contributes to M2 macrophage polarization by acting as an oncogene in ovarian cancer. FCGBP may represent a clinically helpful biomarker for predicting overall survival of ovarian cancer patients.

A bioinformatic analysis: the overexpression and clinical significance of FCGBP in ovarian cancer

Fc fragment of IgG-binding protein (FCGBP) is differentially expressed in various tumors. However, the correlation between FCGBP and immune cell infiltration in ovarian cancer remains unclear. FCGBP expression was analyzed using The Cancer Genome Atlas (TCGA) pan-cancer data, and the ovarian cancer expression profile was analyzed using the Gene Expression Omnibus database. The clinical prognostic value of FCGBP was evaluated using clinical survival data from TCGA. Enrichment analysis of FCGBP was performed using the R package clusterProfiler. Based on known immune cell infiltration scores for samples found in TCGA, we analyzed the association between immune cell infiltration level and FCGBP expression. FCGBP was highly expressed and associated with poorer overall survival (p = 0.00051) and disease-specific survival (p = 0.0012) in ovarian cancer and other tumors. Additionally, high FCGBP expression correlated significantly with immune-related gene sets, including those involved in chemokine signaling pathways and innate and adaptive immunity. Further analysis showed that M2 macrophage infiltration increased and M1 macrophage infiltration decreased in tissues with high FCGBP expression. Our study suggests that FCGBP contributes to M2 macrophage polarization by acting as an oncogene in ovarian cancer. FCGBP may represent a clinically helpful biomarker for predicting overall survival of ovarian cancer patients.

Developing a risk scoring system based on immune-related lncRNAs for patients with gastric cancer

The immune system and the tumor interact closely during tumor development. Aberrantly expressed long non-coding RNAs (lncRNAs) may be potentially applied as diagnostic and prognostic markers for gastric cancer (GC). At present, the diagnosis and treatment of GC patients remain a formidable clinical challenge. The present study aimed to build a risk scoring system to improve the prognosis of GC patients. In the present study, ssGSEA was used to evaluate the infiltration of immune cells in GC tumor tissue samples, and the samples were split into a high immune cell infiltration group and a low immune cell infiltration group. About 1262 differentially expressed lncRNAs between the high immune cell infiltration group and the low immune cell infiltration group. About 3204 differentially expressed lncRNAs between GC tumor tissues and paracancerous tissues were identified. Then, 621 immune-related lncRNAs were screened using a Venn analysis based on the above results, and 85 prognostic lncRNAs were identified using a univariate Cox analysis. We constructed a prognostic signature using LASSO analysis and evaluated the predictive performance of the signature using ROC analysis. GO and KEGG enrichment analyses were performed on the lncRNAs using the R package, ‘clusterProfiler’. The TIMER online database was used to analyze correlations between the risk score and the abundances of the six types of immune cells. In conclusion, our study found that specific immune-related lncRNAs were clinically significant. These lncRNAs were used to construct a reliable prognostic signature and analyzed immune infiltrates, which may assist clinicians in developing individualized treatment strategies for GC patients.

Spondin 2 promotes the proliferation, migration and invasion of gastric cancer cells

Spondin 2 (SPON2), a member of the Mindin F‐Spondin family, identifies pathogens, activates congenital immunity and promotes the growth and adhesion of neurons as well as binding to their receptors, but its role in promoting or inhibiting tumour metastasis is controversial. Here, we investigated its expression levels and mechanism of action in gastric cancer (GC). Western blotting and GC tissue arrays were used to determine the expression levels of SPON2. ELISAs were performed to measure the serum levels of SPON2 in patients with GC. Two GC cell lines expressing low levels of SPON2 were used to analyse the effects of regulating SPON2 expression on proliferation, migration, invasion, the cell cycle and apoptosis. The results revealed that SPON2 was highly expressed in GC tissues from patients with relapse or metastasis. The levels of SPON2 in sera of patients with GC were significantly higher compared with those of healthy individuals and patients with atrophic gastritis. Knockdown of SPON2 expression significantly inhibited the proliferation, migration and invasion of GC cells in vitro and in vivo. Down‐regulation of SPON2 arrested the cell cycle in G1/S, accelerated apoptosis through the mitochondrial pathway and inhibited the epithelial‐mesenchymal transition by blocking activation of the ERK1/2 pathway. In summary, this study suggests that SPON2 acts as an oncogene in the development of GC and may serve as a marker for the diagnosing GC as well as a new therapeutic target for GC.

The important role played by chemokines influence the clinical outcome of Helicobacter pylori infection

The extended infection with Helicobacter pylori (H. pylori), one of the most frequent infectious agents in humans, may cause gastritis, peptic ulcers, gastric mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric cancer. During H. pylori infection, different kinds of inflammatory cells such as dendritic cells, macrophages, neutrophils, mast cells, eosinophils, T cells and B cells are accumulated into the stomach. The interactions between chemokines and their respective receptors recruit particular types of the leukocytes that ultimately determine the nature of immune response and therefore, have a main influence on the consequence of infection. The suitable production of chemokines especially in the early stages of H. pylori infection shapes appropriate immune responses that contribute to the H. pylori elimination. The unbalanced expression of the chemokines can contribute in the induction of inappropriate responses that result in the tissue damage or malignancy. Thus, chemokines and their receptors may be promising potential targets for designing the therapeutic strategies against various types H. pylori-related gastrointestinal disorders. In this review, a comprehensive explanation regarding the roles played by chemokines in H. pylori-mediated peptic ulcer, gastritis and gastric malignancies was provided while presenting the potential utilization of these chemoattractants as therapeutic elements.

Sclerostin domain-containing protein 1 is dispensable for the differentiation of follicular helper and follicular regulatory T cells during acute viral infection

T follicular helper (T_FH) cells are crucial for effective humoral immunity by providing the required signals to cognate B cells and promoting germinal center (GC) formation. Many intrinsic and extrinsic factors have been reported to be involved in the multistage, multifactorial differentiation process of T_FH cells. By comparing gene expression between T_FH cells and T_H1 cells based on published GEO data, we found selective and high expression of sclerostin domain-containing protein 1 (SOSTDC1) in T_FH cells but not in T_H1 cells; however, it is unclear whether SOSTDC1 is important for the differentiation and/or function of T_FH cells. Using a mouse model of acute lymphocytic choriomeningitis virus (LCMV) infection, we confirmed the selective expression of SOSTDC1 in T_FH cells compared to that in T_H1 cells, but the ablation of SOSTDC1 did not affect T_FH cell differentiation or effector function. Thus, our results indicate that the SOSTDC1 protein is merely a specific marker of T_FH cells but does not play a functional role in the differentiation of T_FH cells during acute viral infection.

A targeted proteomics approach reveals a serum protein signature as diagnostic biomarker for resectable gastric cancer

BACKGROUND

Gastric cancer (GC) is the third leading cause of cancer death. Early detection is a key factor to reduce its mortality.

METHODS

We retrospectively collected pre- and postoperative serum samples as well as tumour tissues and adjacent normal tissues from 100 GC patients. Serum samples from non-cancerous patients were served as controls (n = 50). A high-throughput protein detection technology, multiplex proximity extension assays (PEA), was applied to measure levels of over 300 proteins. Alteration of each protein was analysed by univariate analysis. Elastic-net logistic regression was performed to select serum proteins into the diagnostic model.

FINDINGS

We identified 19 serum proteins (CEACAM5, CA9, MSLN, CCL20, SCF, TGF-alpha, MMP-1, MMP-10, IGF-1, CDCP1, PPIA, DDAH-1, HMOX-1, FLI1, IL-7, ZBTB-17, APBB1IP, KAZALD-1, and ADAMTS-15) that together distinguish GC cases from controls with a diagnostic sensitivity of 93%, specificity of 100%, and area under receiver operating characteristic curve (AUC) of 0·99 (95% CI: 0·98-1). Moreover, the 19-serum protein signature provided an increased diagnostic capacity in patients at TNM I-II stage (sensitivity 89%, specificity 100%, AUC 0·99) and in patients with high microsatellite instability (MSI) (91%, 98%, and 0·99) compared to individual proteins. These promising results will inspire a large-scale independent cohort study to be pursued for validating the proposed protein signature.

INTERPRETATION

Based on targeted proteomics and elastic-net logistic regression, we identified a 19-serum protein signature which could contribute to clinical GC diagnosis, especially for patients at early stage and those with high MSI. FUND: This study was supported by a European H2020-Marie Skłodowska-Curie Innovative Training Networks grant (316,929, GastricGlycoExplorer). Funder had no influence on trial design, data evaluation, and interpretation.

A risk score model for the prediction of osteosarcoma metastasis

Osteosarcoma is the most common primary solid malignancy of the bone, and its high mortality usually correlates with early metastasis. In this study, we developed a risk score model to help predict metastasis at the time of diagnosis. We downloaded and mined four expression profile datasets associated with osteosarcoma metastasis from the Gene Expression Omnibus. After data normalization, we performed LASSO logistic regression analysis together with 10-fold cross validation using the GSE21257 dataset. A combination of eight genes (RAB1,CLEC3B,FCGBP,RNASE3,MDL1,ALOX5AP,VMO1 and ALPK3) were identified as being associated with osteosarcoma metastasis. These genes were put into a gene risk score model, and the prediction efficiency of the model was then validated using three independent datasets (GSE33383, GSE66673, and GSE49003) by plotting receiver operating characteristic curves. The expression levels of the eight genes in all datasets were shown as heatmaps, and gene ontology gene annotation and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were performed. These eight genes play a role in cancer-related biological processes, such as apoptosis and biosynthetic processes. Our results may aid in elucidating the possible mechanisms of osteosarcoma metastasis, and may help to facilitate the individual management of patients with osteosarcoma after treatment.

Development of somatic mutation signatures for risk stratification and prognosis in lung and colorectal adenocarcinomas

Background

Prognostic signatures are vital to precision medicine. However, development of somatic mutation prognostic signatures for cancers remains a challenge. In this study we developed a novel method for discovering somatic mutation based prognostic signatures.

Results

Somatic mutation and clinical data for lung adenocarcinoma (LUAD) and colorectal adenocarcinoma (COAD) from The Cancer Genome Atlas (TCGA) were randomly divided into training (n = 328 for LUAD and 286 for COAD) and validation (n = 167 for LUAD and 141 for COAD) datasets. A novel method of using the log2 ratio of the tumor mutation frequency to the paired normal mutation frequency is computed for each patient and missense mutation. The missense mutation ratios were mean aggregated into gene-level somatic mutation profiles. The somatic mutations were assessed using univariate Cox analysis on the LUAD and COAD training sets separately. Stepwise multivariate Cox analysis resulted in a final gene prognostic signature for LUAD and COAD. Performance was compared to gene prognostic signatures generated using the same pipeline but with different somatic mutation profile representations based on tumor mutation frequency, binary calls, and gene-gene network normalization. Signature high-risk LUAD and COAD cases had worse overall survival compared to the signature low-risk cases in the validation set (log-rank test p-value = 0.0101 for LUAD and 0.0314 for COAD) using mutation tumor frequency ratio (MFR) profiles, while all other methods, including gene-gene network normalization, have statistically insignificant stratification (log-rank test p-value ≥0.05). Most of the genes in the final gene signatures using MFR profiles are cancer-related based on network and literature analysis.

Conclusions

We demonstrated the robustness of MFR profiles and its potential to be a powerful prognostic tool in cancer. The results are robust according to validation testing and the selected genes are biologically relevant.

Spondin-2 is a novel diagnostic biomarker for laryngeal squamous cell carcinoma

Spondin-2, belongs to the SOX (SRY-related HMG box) gene family, plays a vital role in the development of malignancy, however, the role of Spondin-2 in laryngeal squamous cell carcinoma (LSCC) remains unknown. The aim of this study is to investigate the prognostic significance of and probable mechanism of Spondin-2 in LSCC. qRT-PCR, western blotting assays and IHC analysis demonstrated that Spondin-2 was significantly increased in LSCC tissues compared with adjacent non-tumorous tissues. In addition, high levels of Spondin-2 was associated with clinical stage, lymph node metastasis and pathology grade of LSCC patients (P ＜0.05). Kaplan-Meier analysis showed that patients with high expression of Spondin-2 had a lower overall survival rate (P＜0.05) than that with low expression of Spondin-2. Moreover, spondin-2 silencing inhibited the proliferation of LSCC cells through inhibiting the activation of PI3K/AKT signaling. In conclusion, spondin-2 might be a novel therapeutic target and prognostic biomarker for LSCC patients.

Upregulation of Spondin-2 protein expression correlates with poor prognosis in hepatocellular carcinoma

OBJECTIVE

The aim of this study was to measure the extracellular matrix protein Spondin-2 (SPON2) in hepatocellular carcinoma (HCC) tissues and to determine its potential value as a prognostic indicator by assessing its correlation with clinicopathological variables and survival.

METHODS

SPON2 mRNA expression was assessed in 20 matched pairs of HCC and non-cancerous liver tissues by quantitative reverse transcription-polymerase chain reaction analysis. SPON2 protein expression was determined in 107 matched pairs of HCC and normal liver tissue by immunohistochemical staining of tissue microarrays.

RESULTS

Analysis of patient tissues and Oncomine datasets showed that SPON2 mRNA and SPON2 protein expression were both significantly upregulated in HCC tissues, compared with non-cancerous liver tissue; moreover, both correlated significantly with tumor size. Kaplan-Meier analysis revealed that HCC patients who showed high levels of cytoplasmic SPON2 protein had poorer survival following curative resection, compared with HCC patients who exhibited low protein expression levels. Multivariate Cox regression analysis showed that tumor thrombus and SPON2 protein expression both independently correlated with reduced survival in HCC patients.

CONCLUSION

Upregulated expression of SPON2 protein in tumor tissue could be an effective prognostic indicator for patients with HCC.

E4BP4 promotes thyroid cancer proliferation by modulating iron homeostasis through repression of hepcidin

Iron homeostasis is critical to mammals, and dysregulation in iron homeostasis usually leads to severe disorders including various cancers. Massive hepcidin secretion is an indicator of thyroid cancer, but the molecular mechanisms responsible for this dysregulation are unknown. Hepcidin secretion from thyroid cancer cells also leads to decreased expression of the iron exporter, ferroportin (FPN), and increased intracellular iron retention, which promote cancer proliferation. In this study, we examined the role of hepcidin in thyroid cancer (TC) and the molecular bases of its signaling. Synthesis of hepcidin is regulated by the BMP4/7 agonist SOSTDC1, which was downregulated in TC; SOSTDC1 downregulation was correlated with G9a-mediated hypermethylation in its promoter. The binding of G9a to the SOSTDC1 promoter requires E4BP4, which interacts with G9a to form a multi-molecular complex that contributes to SOSTDC1 silencing. Silencing of E4BP4 or G9a has similar effects to SOSTDC1 overexpression, which suppresses secretion of hepcidin and inhibits TC cell proliferation. Furthermore, our in vivo xenograft data indicated that depletion of E4BP4 also inhibits cancer growth, reduces hepcidin secretion, and reduces G9a nuclear transportation. Iron homeostasis and tumor growth in TC may be regulated by an E4BP4-dependent epigenetic mechanism. These findings suggest a new mechanism of cellular iron dysfunction through the E4BP4/G9a/SOSTDC1/hepcidin pathway, which is an essential link in TC.

Silencing non-SMC chromosome-associated polypeptide G inhibits proliferation and induces apoptosis in hepatocellular carcinoma cells

The present study was designed to investigate the significance of non-structural maintenance of chromosomes (non-SMC) chromosome-associated polypeptide G (NCAPG), a subunit of condensin complex I, in the development of hepatocellular carcinoma (HCC). NCAPG protein expression in human HCC and paracancerous hepatic tissues were examined using immunohistochemistry, and NCAPG mRNA expression in HCC cell lines were quantified using quantitative RT-PCR. Lentivirus-mediated RNA interference was used to silence NCAPG in HCC cells. Cell proliferation was monitored by MTT assay. Cell colony-forming capacity was measured by colony formation assay. Apoptosis was determined by flow cytometry. The results showed that increased protein expression of NCAPG was found in HCC tissues compared with the matched paracancerous hepatic tissues. At the mRNA level, increased expression of NCAPG was found in HCC cells as opposed to the normal hepatocytes. Silencing of NCAPG in BEL-7404 and SMMC-7721 cells led to decreased cell proliferation and increased apoptosis. These changes were associated with increased mRNA expressions of P53, P27, and Bad, but decreased mRNA expression of EGFR, Akt, survivin, and JNK. NCAPG might play an oncogenic role in the development of liver cancer. Further studies to clarify its role and underlying mechanisms in the development of liver cancer are warranted.

Inflammatory cytokines are associated with response and prognosis in patients with esophageal cancer

Background

Esophageal cancer is often marked by aggressive tumor growth and poor prognosis. Patient groups who benefit from perioperative therapy are not yet defined. The tumor microenvironment and circulating factors as possible predictors of response and prognosis gain interest. This study aimed to investigate cytokines in patients’ serum and tumor tissue with regard to response and prognosis.

Results

Median survival between SCC and AC was not different (published previously). Lower levels of CCL11 (Eotaxin-1) and CXCL10 (IP-10) in the tumor tissue were associated with a better prognosis (p = 0.022; p = 0.002). In the AC subgroup higher concentrations of TGF-β3 in serum and corresponding tumor tissue were associated with adverse prognosis (p = 0.035; p = 0.006). An association with histopathological response was found for IL-12(p70) and CXCL10 in patients’ sera (p = 0.041; p = 0.032). The tissue levels of TGF-β1 and TGF-β2 were significantly lower in histopathological responders than in nonresponders (p = 0.033; p = 0.007). A similar trend was seen for TGF-β3, without statistical significance (p = 0.097).

Materials and Methods

Preoperative serum samples and corresponding tumor tissue (n = 54), only serum (n = 20) or only tissue (n = 4) were collected from patients undergoing surgery for cT3/4 esophageal squamous cell cancer (SCC) (n = 34) and adenocarcinoma (AC) (n = 44). All samples were taken after neoadjuvant treatment. All patients received perioperative chemo(radio)therapy. Cytokine levels of 17 different cytokines were measured by multiplex immunoassay and correlated with clinicopathological factors.

Conclusions

Two chemokines (CCL11 and CXCL10) in posttherapeutic tumor tissue were associated with prognosis in patients with esophageal cancer, lower levels indicating a better prognosis. Lower levels of TGF-β were associated with better response and prognosis in patients with AC.

Native and bone marrow-derived cell mosaicism in gastric carcinoma in H. pylori-infected p27-deficient mice

Objective

Chronic Helicobacter pylori (H. pylori) infection promotes non-cardia gastric cancer. Some mouse models suggest that bone marrow derived cells (BMDC) contribute to Helicobacter-associated gastric carcinogenesis. We determined whether this increased susceptibility to Helicobacter-induced gastric carcinogenesis of p27-deficient mice is dependent upon their p27-null BMDC or their p27-null gastric epithelial cells.

Design

Female mice (recipients) were irradiated and transplanted with BMDC from male donors. Wild type (WT) mice in group 1 (control) received BMDC from male GFP-transgenic mice. Female WT and p27 KO mice were engrafted with male p27KO mice BMDC (Group 2) or GFP-transgenic WT BMDC (Group 3). Recipients were infected with H. pylori SS1 for one year.

Results

Mice lacking p27 in either the BM pool or gastric epithelium developed significantly more advanced gastric pathology, including high-grade dysplasia. Co-staining of donor BMDC in dysplastic gastric glands was confirmed by immunofluorescence. Gastric expression of IL-1 beta protein was reduced in groups 2 and 3 (p < 0.05 vs control) whereas expression of IFN-γ and chemokines MIP-1 beta, MIG, IP-10 and RANTES in group 2 were significantly higher than group 3.

Conclusions

Both bone marrow-derived and gastric epithelial cells contribute to the increased gastric cancer susceptibility of p27-deficient H. pylori-infected mice.

Elevated spondin-2 expression correlates with progression and prognosis in gastric cancer

The spondin-2 correlated with tumor progression in many malignancies. However, the role of spondin-2 in gastric cancer has not been thoroughly elucidated. Spondin-2 and matrix metallopeptidase 9 (MMP-9) expression was detected by immunohistochemistry in 174 gastric carcinoma tissues. The relationship between the expression of spondin-2 and MMP-9, clinicopathological/prognostic value in gastric cancer was examined. Spondin-2 was significantly higher in gastric cancer than that in adjacent non-tumorous tissues. Spondin-2 overexpression was significantly associated with well differentiation, depth of invasion, lymph node metastasis, and advanced TNM stages. The expression levels of spondin-2 were increasing in both prominent serosal invasion group and lymph node metastasis group. In addition, spondin-2 was positively correlated with MMP-9 among 174 gastric cancer samples. In univariate and multivariate analyses, spondin-2 was an independent prognostic factor for both recurrence-free survival (RFS) and overall survival (OS). Moreover, spondin-2 overexpression was associated with poor prognosis in patients with gastric cancer in different risk groups. In conclusion, Spondin-2 overexpression contributes to tumor aggressiveness and prognosis, and could be a promising target for prognostic prediction in gastric cancer patients.

A novel gene expression-based prognostic scoring system to predict survival in gastric cancer

Analysis of gene expression patterns in gastric cancer (GC) can help to identify a comprehensive panel of gene biomarkers for predicting clinical outcomes and to discover potential new therapeutic targets. Here, a multi-step bioinformatics analytic approach was developed to establish a novel prognostic scoring system for GC. We first identified 276 genes that were robustly differentially expressed between normal and GC tissues, of which, 249 were found to be significantly associated with overall survival (OS) by univariate Cox regression analysis. The biological functions of 249 genes are related to cell cycle, RNA/ncRNA process, acetylation and extracellular matrix organization. A network was generated for view of the gene expression architecture of 249 genes in 265 GCs. Finally, we applied a canonical discriminant analysis approach to identify a 53-gene signature and a prognostic scoring system was established based on a canonical discriminant function of 53 genes. The prognostic scores strongly predicted patients with GC to have either a poor or good OS. Our study raises the prospect that the practicality of GC patient prognosis can be assessed by this prognostic scoring system.

A common molecular signature of intestinal-type gastric carcinoma indicates processes related to gastric carcinogenesis

Gastric carcinoma (GC) is one of the most aggressive cancers and the second leading cause of cancer death in the world. According to the Lauren classification, this adenocarcinoma is divided into two subtypes, intestinal and diffuse, which differ in their clinical, epidemiological and molecular features. Several studies have attempted to delineate the molecular signature of gastric cancer to develop new and non-invasive screening tests that improve diagnosis and lead to new treatment strategies. However, a consensus signature has not yet been identified for each condition. Thus, this work aimed to analyze the gene expression profile of Brazilian intestinal-type GC tissues using microarrays and compare the results to those of non-tumor tissue samples. Moreover, we compared our intestinal-type gastric carcinoma profile with those obtained from populations worldwide to assess their similarity. The results identified a molecular signature for intestinal-type GC and revealed that 38 genes differentially expressed in Brazilian intestinal-type gastric carcinoma samples can successfully distinguish gastric tumors from non-tumor tissue in the global population. These differentially expressed genes participate in biological processes important to cell homeostasis. Furthermore, Kaplan-Meier analysis suggested that 7 of these genes could individually be able to predict overall survival in intestinal-type gastric cancer patients.

The dual role of asporin in breast cancer progression

Asporin has been reported as a tumor suppressor in breast cancer, while asporin-activated invasion has been described in gastric cancer. According to our in silico search, high asporin expresion associates with significantly better relapse free survival (RFS) in patients with low-grade tumors but RFS is significantly worse in patients with grade 3 tumors. In line with other studies, we have confirmed asporin expression by RNA scope in situ hybridization in cancer associated fibroblasts. We have also found asporin expression in the Hs578T breast cancer cell line which we confirmed by quantitative RT-PCR and western blotting. From multiple testing, we found that asporin can be downregulated by bone morphogenetic protein 4 while upregulation may be facilited by serum-free cultivation or by three dimensional growth in stiff Alvetex scaffold. Downregulation by shRNA inhibited invasion of Hs578T as well as of CAFs and T47D cells. Invasion of asporin-negative MDA-MB-231 and BT549 breast cancer cells through collagen type I was enhanced by recombinant asporin. Besides other investigations, large scale analysis of aspartic acid repeat polymorphism will be needed for clarification of the asporin dual role in progression of breast cancer.

The Homeotic Protein SIX3 Suppresses Carcinogenesis and Metastasis through Recruiting the LSD1/NuRD(MTA3) Complex

The homeodomain transcription factor SIX3 was recently reported to be a negative regulator of the Wnt pathway and has an emerging role in cancer. However, how SIX3 contributes to tumorigenesis and metastasis is poorly understood.

METHODS

We employed affinity purification and mass spectrometry (MS) to identify the proteins physically associated with SIX3. Genome-wide analysis of the SIX3/LSD1/NuRD(MTA3) complex using a chromatin immunoprecipitation-on-chip approach identified a cohort of target genes including WNT1 and FOXC2, which are critically involved in cell proliferation and epithelial-to-mesenchymal transition. Also, we used flow cytometry, growth curve analysis, EdU incorporation assay, colony formation assays, trans-well invasion assays, immunohistochemical staining and in vivo bioluminescence assay to investigate the function of SIX3 in tumorigenesis.

RESULTS

We demonstrate that the SIX3/LSD1/NuRD(MTA3) complex inhibits carcinogenesis in breast cancer cells and suppresses metastasis in breast cancer. SIX3 expression is downregulated in various human cancers and high SIX3 is correlated with improved prognosis.

CONCLUSION

Our study revealed an important mechanistic link between the loss of function of SIX3 and tumor progression, identified a molecular basis for the opposing actions of MTA1 and MTA3, and may provide new potential prognostic indicators and targets for cancer therapy.

Low density lipoprotein receptor class A domain containing 4 (LDLRAD4) promotes tumorigenesis of hepatic cancer cells

LDLRAD4 was previously identified and shown to be connected with psychiatric disorders. The structure of LDLRAD4 protein is similar to that of TMEPAI protein, which is overexpressed in many tumors. However, it is still unknown whether LDLRAD4 is involved in tumorigenesis. In this study, the potential role of LDLRAD4 in tumorigenesis was investigated. LDLRAD4 is elevated in hepatic cancer cells and tumor tissues, and expression of LDLRAD4 promotes hepatic cancer cell HepG2 and SMMC-7721 proliferation and migration. LDLRAD4 interacts Nedd4 to promote cell proliferation and migration and negatively regulates the TGF-β signaling. Furthermore, immunofluorescence microscopy analysis indicates that LDLRAD4 is localized to the lysosome and association with Nedd4 is necessary for its intracellular transport to the lysosome. In addition, depletion of LDLRAD4 in HepG2 liver cancer cells inhibited tumorigenesis in nude mice. These results reveal an oncogenic role of LDLRAD4 in tumorigenesis through its association with Nedd4.

Predictive model for inflammation grades of chronic hepatitis B: Large-scale analysis of clinical parameters and gene expressions

BACKGROUND

Liver biopsy is the gold standard to assess pathological features (eg inflammation grades) for hepatitis B virus-infected patients although it is invasive and traumatic; meanwhile, several gene profiles of chronic hepatitis B (CHB) have been separately described in relatively small hepatitis B virus (HBV)-infected samples. We aimed to analyse correlations among inflammation grades, gene expressions and clinical parameters (serum alanine amino transaminase, aspartate amino transaminase and HBV-DNA) in large-scale CHB samples and to predict inflammation grades by using clinical parameters and/or gene expressions.

METHODS

We analysed gene expressions with three clinical parameters in 122 CHB samples by an improved regression model. Principal component analysis and machine-learning methods including Random Forest, K-nearest neighbour and support vector machine were used for analysis and further diagnosis models. Six normal samples were conducted to validate the predictive model.

RESULTS

Significant genes related to clinical parameters were found enriching in the immune system, interferon-stimulated, regulation of cytokine production, anti-apoptosis, and etc. A panel of these genes with clinical parameters can effectively predict binary classifications of inflammation grade (area under the ROC curve [AUC]: 0.88, 95% confidence interval [CI]: 0.77-0.93), validated by normal samples. A panel with only clinical parameters was also valuable (AUC: 0.78, 95% CI: 0.65-0.86), indicating that liquid biopsy method for detecting the pathology of CHB is possible.

CONCLUSIONS

This is the first study to systematically elucidate the relationships among gene expressions, clinical parameters and pathological inflammation grades in CHB, and to build models predicting inflammation grades by gene expressions and/or clinical parameters as well.

Tumor Trp53 status and genotype affect the bone marrow microenvironment in acute myeloid leukemia

The genetic heterogeneity of acute myeloid leukemia (AML) and the variable responses of individual patients to therapy suggest that different AML genotypes may influence the bone marrow (BM) microenvironment in different ways. We performed gene expression profiling of bone marrow mesenchymal stromal cells (BM-MSC) isolated from normal C57BL/6 mice or mice inoculated with syngeneic murine leukemia cells carrying different human AML genotypes, developed in mice with Trp53 wild-type or nullgenetic backgrounds. We identified a set of genes whose expression in BM-MSC was modulated by all four AML genotypes tested. In addition, there were sets of differentially-expressed genes in AML-exposed BM-MSC that were unique to the particular AML genotype or Trp53 status. Our findings support the hypothesis that leukemia cells alter the transcriptome of surrounding BM stromal cells, in both common and genotype-specific ways. These changes are likely to be advantageous to AML cells, affecting disease progression and response to chemotherapy, and suggest opportunities for stroma-targeting therapy, including those based on AML genotype.

Identification of extracellular matrix protein 1 as a potential plasma biomarker of ESCC by proteomic analysis using iTRAQ and 2D-LC-MS/MS

PURPOSE

This study was aimed to conduct a proteomics profiling analysis on plasma obtained from ESCC patients with the goal of identifying appropriate plasma protein biomarkers in the progression of ESCC.

EXPERIMENTAL DESIGN

Plasma from 28 ESCC patients and 28 healthy controls (HC) were analyzed by iTRAQ combined with 2D-LC-MS/MS. ProteinPilot software was used to identify the differentially expressed plasma proteins in ESCC compared to HC. Western blot was performed to verify the expression of selected proteins in 37 independent ESCC patients and 37 HC. Transwell and MTT assays were used to detect the biological function of ECM1 protein in vitro.

RESULTS

Nineteen (four upregulated and fifteen downregulated) proteins were identified as differentially expressed between ESCC and HC (p <0.05). Biological functions of these proteins are involved in cell adhesion, cell apoptosis and metabolic processes, visual perception and immune response. Of these, extracellular matrix 1 (ECM1) and lumican (LUM) were selected further confirmation by Western blot (p <0.05), which were consistent with the iTRAQ results. Furthermore, the migration ability of EC9706 cell line after overexpressing ECM1 was increased significantly (p <0.05). The proliferation ability of HUVEC cell was enhanced when treated with the culture supernatants of EC9706 overexpressed ECM1(p <0.05).

CONCLUSION AND CLINICAL RELEVANCE

This proteome analysis indicate that ECM1 is a potential novel plasma protein biomarker for the detection of primary ESCC and evaluation of neoplasms progression.

Silencing of ATP4B of ATPase H+/K+ Transporting Beta Subunit by Intragenic Epigenetic Alteration in Human Gastric Cancer Cells

The ATPase H+/K+ Transporting Beta Subunit (ATP4B) encodes the β subunit of the gastric H+, K+-ATPase, which controls gastric acid secretion and is therefore a target for acid reduction. Downregulation of ATP4B was recently observed in human gastric cancer (GC) without known mechanisms. In the present study, we demonstrated that ATP4B expression was decreased in human GC tissues and cell lines associated with DNA hypermethylation and histone hypoacetylation of histone H3 lysine 9 at its intragenic region close to the transcriptional start site. The expression of ATP4B was restored in GC cell lines by treatment with the DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine (5-AZA), or histone deacetylase inhibitor, trichostatin A (TSA), with further enhancement by combined treatment with both drugs. In contrast, 5-AZA had no effect on ATP4B expression in human hepatocellular carcinoma (HCC) and pancreatic cancer cell lines, in which ATP4B was silenced and accompanied by intragenic methylation. Chromatin immunoprecipitation (ChIP) showed that, in BGC823 GC cells, histone H3 lysine 9 acetylation (H3K9ac) was enhanced in the intragenic region of ATP4B upon TSA treatment, whereas 5-AZA showed a minimal effect. Additionally, ATP4B expression enhanced the inhibitory effects of chemotherapeutic mediation docetaxel on GC cell growth. Thus, as opposed to HCC and pancreatic cancer cells, the silencing of ATP4B in GC cells is attributable to the interplay between intragenic DNA methylation and histone acetylation of ATP4B, the restoration of which is associated with a favorable anticancer effect of docetaxel. These results have implications for targeting epigenetic alteration at the intragenic region of ATP4B in GC cells to benefit diagnosis and treatment of GC.

Elevated level of some chemokines in plasma of gastric cancer patients

INTRODUCTION

Gastric cancer is one of the most common cancer-related causes of death. This is mainly due to the lack of good noninvasive method/biomarkers suitable for early-tumour diagnosis and planning of further therapy modalities. Chemokines play an important role in cancer progression and metastasis formation. In gastric cancer patients, clinical relevance of CXCL12 and CCL5 level has been postulated.

AIM OF THE STUDY

Efforts were undertaken to examine whether expanded chemokine range may be relevant for evaluation of preoperative staging of gastric cancer patients.

MATERIAL AND METHODS

Plasma from 66 gastric cancer patients and 11 healthy controls was obtained, and CCL2, CCL3, CCL4, CCL5, CXCL8, CXCL9, and CXCL10 levels were determined by flow cytometry FlexSet system.

RESULTS

In gastric cancer patients' plasma an increased level of CCL2, CCL4, CCL5, CXCL8, CXCL9, and CXCL10 was observed. In the case of CCL2, CXCL9, and CXCL10, the chemokine levels correlated with advanced (III and IV in TNM classification) disease stage. In the case of CCL4, CCL5, and CXCL8, elevated levels were observed in all cancer patients in comparison to healthy donors.

CONCLUSIONS

The accuracy of preoperative diagnosis in gastric cancer may include the monitoring of a wide range of chemokines in patients' plasma. Increased levels of chemokines may warn that the disease is more advanced than conventional diagnostic procedures suggest.

Intrinsic disorder in spondins and some of their interacting partners

Spondins, which are proteins that inhibit and promote adherence of embryonic cells so as to aid axonal growth are part of the thrombospondin-1 family. Spondins function in several important biological processes, such as apoptosis, angiogenesis, etc. Spondins constitute a thrombospondin subfamily that includes F-spondin, a protein that interacts with Aβ precursor protein and inhibits its proteolytic processing; R-spondin, a 4-membered group of proteins that regulates Wnt pathway and have other functions, such as regulation of kidney proliferation, induction of epithelial proliferation, the tumor suppressant action; M-spondin that mediates mechanical linkage between the muscles and apodemes; and the SCO-spondin, a protein important for neuronal development. In this study, we investigated intrinsic disorder status of human spondins and their interacting partners, such as members of the LRP family, LGR family, Frizzled family, and several other binding partners in order to establish the existence and importance of disordered regions in spondins and their interacting partners by conducting a detailed analysis of their sequences, finding disordered regions, and establishing a correlation between their structure and biological functions.

Immunohistochemical expression and localization of cytokines/chemokines/growth factors in gastric cancer

Our previous studies on gastric cancer tissue and patient plasma samples identified several cytokines/chemokines/growth factors to be differentially expressed, compared to normal samples. In this study our aim was to understand the localization patterns of the markers in gastric tissues. We investigated the expression of PDGFRB, CCL3, MMP3, CXCL8, CXCL10, CCL20, IGFBP3, CXCL9, SPP1, CCL18, TIMP1, CCL15, CXCL5 and CCL4 in gastric tissues using Immunohistochemistry (IHC) on Tissue Microarrays (TMA). The TMA comprised of 25 apparently normal (AN), 87 paired normal (PN) and 134 gastric cancer (T) tissues. The epithelial and stromal expression of markers and their correlation with patient characteristics and outcome were analyzed. Several of the markers [PDGFRB (p<0.001), CCL3 (p<0.001), MMP3 (p<0.001), CXCL8 (p<0.001), CXCL10 (p<0.001), CCL20 (p<0.001), CXCL9 (p<0.001), CCL18 (p<0.001), TIMP1 (p=0.025), CCL15 (p<0.001)] were elevated in the stromal compartment of gastric cancers compared to AN tissues, with some having intermediate levels of expression in PN tissues. Epithelial and stromal PDGFRB (p=0.030, p=0.018) expression was associated with diffuse type gastric cancer. Stromal IGFBP3 (p=0.039), CXCL8 (p=0.008), TIMP1 (p<0.001), CCL4 (p=0.003) and SPP1 (p=0.048) expression was associated with intestinal type gastric cancer. Kaplan-Meier analysis showed higher epithelial PDGFRB (p=0.005 and p=0.004), CXCL8 (p=0.009 and p=0.007) were associated with poor disease free and overall survival. In multivariate analysis, high epithelial PDGFRB (p=0.036 and p=0.02) and SPP1 (p=0.003 and p<0.001) were independent prognostic factors for DFS and OS in patients with gastric cancer. The expression of cytokine/chemokine/growth factor markers is higher in the gastric tumor stroma compared to the normal gastric stroma and PDGFRB and SPP1 may serve as potential prognostic factors in gastric cancer.