The tumor suppressor semaphorin 3B triggers a prometastatic program mediated by interleukin 8 and the tumor microenvironment

Impact and potential value of immunosenescence on solid gastrointestinal tumors

Solid gastrointestinal tumors often respond poorly to immunotherapy for the complex tumor microenvironment (TME), which is exacerbated by immune system alterations. Immunosenescence is the process of increased diversification of immune genes due to aging and other factors, leading to a decrease in the recognition function of the immune system. This process involves immune organs, immune cells, and the senescence-associated secretory phenotype (SASP). The most fundamental change is DNA damage, resulting in TME remodeling. The main manifestations are worsening inflammation, increased immunosuppressive SASP production, decreased immune cell antitumor activity, and the accumulation of tumor-associated fibroblasts and myeloid-derived suppressor cells, making antitumor therapy less effective. Senotherapy strategies to remove senescent cells and block key senescence processes can have synergistic effects with other treatments. This review focuses on immunoenescence and its impact on the solid TME. We characterize the immunosenescent TME and discuss future directions for antitumor therapies targeting senescence.

Semaphorins in tumor microenvironment: Biological mechanisms and therapeutic progress

Hallmark features of the tumor microenvironment include immune cells, stromal cells, blood vessels, and extracellular matrix (ECM), providing a conducive environment for the growth and survival of tumors. Recent advances in the understanding of cancer biology have highlighted the functional role of semaphorins (SEMAs). SEMAs are a large and diverse family of widely expressed secreted and membrane-binding proteins, which were initially implicated in axon guidance and neural development. However, it is now clear that they are widely expressed beyond the nervous system and participate in regulating immune responses and cancer progression. In fact, accumulating evidence disclosed that different SEMAs can either stimulate or restrict tumor progression, some of which act as important regulators of tumor angiogenesis. Conversely, limited information is known about the functional relevance of SEMA signals in TME. In this setting, we systematically elaborate the role SEMAs and their major receptors played in characterized components of TME. Furthermore, we provide a convergent view of current SEMAs pharmacological progress in clinical treatment and also put forward their potential application value and clinical prospects in the future.

SEMA3B-AS1 suppresses colorectal carcinoma progression by inhibiting Semaphorin 3B-dependent VEGF signaling pathway activation

Mounting evidence has demonstrated the considerable regulatory effects of long noncoding RNAs (lncRNAs) in the tumorigenesis and progression of various carcinomas. LncRNA Semaphorin 3B (SEMA3B) antisense RNA 1 (SEMA3B-AS1) has been found to be dysregulated in a few carcinomas recently. However, its potential function and mechanism in colorectal carcinoma (CRC) have not yet been examined. Here we show that SEMA3B-AS1 acts as a crucial regulator of CRC progression. We found that SEMA3B-AS1 expression was downregulated in CRC cell lines and tissues. Downregulation of SEMA3B-AS1 was significantly associated with poor survival in CRC patients. Overexpression of SEMA3B-AS1 reduced the cell growth and metastasis of CRC in vivo and in vitro. In addition, SEMA3B-AS1 promoted the expression of its sense-cognate gene SEMA3B, a member of the Semaphorin family (SEMAs), by recruiting EP300 to induce H3K9 acetylation at the SEMA3B promoter. Furthermore, we proved that SEMA3B-AS1 suppressed CRC angiogenesis by affecting the vascular endothelial growth factor signaling pathway activation which was regulated by the SEMA3B-NRP1 axis. Our work unravels a novel mechanism of SEMA3B-AS1 in the inhibition of CRC malignant progression and highlights its probability as a new promising diagnostic marker and therapeutic target for CRC interventions.

Emerging roles and mechanisms of semaphorins activity in cancer

Semaphorins are regulatory molecules that are linked to the modulation of several cancer processes, such as angiogenesis, cancer cell invasiveness and metastasis, tumor growth, as well as cancer cell survival. Semaphorin (SEMA) activity depends on the cancer histotypes and their particularities. In broad terms, the effects of SEMAs result from their interaction with specific receptors/co-receptors - Plexins, Neuropilins and Integrins - and the subsequent effects upon the downstream effectors (e.g. PI3K/AKT, MAPK/ERK). The present article serves as an integrative review work, discussing the broad implications of semaphorins in cancer, focusing on cell proliferation/survival, angiogenesis, invasion, metastasis, stemness, and chemo-resistance/response whilst highlighting their heterogeneity as a family. Herein, we emphasized that semaphorins are largely implicated in cancer progression, interacting with the tumor microenvironment components. Whilst some SEMAs (e.g. SEMA3A, SEMA3B) function widely as tumor suppressors, others (e.g. SEMA3C) act as pro-tumor semaphorins. The differences observed in terms of the biological structure of SEMAs and the particularities of each cancer histotypes require that each semaphorin be viewed as a unique entity, and its roles must be researched accordingly. A more in-depth and comprehensive view of the molecular mechanisms that promote and sustain the malignant behavior of cancer cells is of utmost importance.

SEMA6A/RhoA/YAP axis mediates tumor-stroma interactions and prevents response to dual BRAF/MEK inhibition in BRAF-mutant melanoma

Background

Despite the promise of dual BRAF/MEK inhibition as a therapy for BRAF-mutant (BRAF-mut) melanoma, heterogeneous responses have been observed in patients, thus predictors of benefit from therapy are needed. We have previously identified semaphorin 6A (SEMA6A) as a BRAF-mut-associated protein involved in actin cytoskeleton remodeling. The purpose of the present study is to dissect the role of SEMA6A in the biology of BRAF-mut melanoma, and to explore its predictive potential towards dual BRAF/MEK inhibition.

Methods

SEMA6A expression was assessed by immunohistochemistry in melanoma cohort RECI1 (N = 112) and its prognostic potential was investigated in BRAF-mut melanoma patients from DFCI and TCGA datasets (N = 258). The molecular mechanisms regulated by SEMA6A to sustain tumor aggressiveness and targeted therapy resistance were investigated in vitro by using BRAF-mut and BRAF-wt melanoma cell lines, an inducible SEMA6A silencing cell model and a microenvironment-mimicking fibroblasts-coculturing model. Finally, SEMA6A prediction of benefit from dual BRAF/MEK inhibition was investigated in melanoma cohort RECI2 (N = 14).

Results

Our results indicate higher protein expression of SEMA6A in BRAF-mut compared with BRAF-wt melanoma patients and show that SEMA6A is a prognostic indicator in BRAF-mut melanoma from TCGA and DFCI patients cohorts. In BRAF-mut melanoma cells, SEMA6A coordinates actin cytoskeleton remodeling by the RhoA-dependent activation of YAP and dual BRAF/MEK inhibition by dabrafenib+trametinib induces SEMA6A/RhoA/YAP axis. In microenvironment-mimicking co-culture condition, fibroblasts confer to melanoma cells a proliferative stimulus and protect them from targeted therapies, whereas SEMA6A depletion rescues the efficacy of dual BRAF/MEK inhibition. Finally, in BRAF-mut melanoma patients treated with dabrafenib+trametinib, high SEMA6A predicts shorter recurrence-free interval.

Conclusions

Overall, our results indicate that SEMA6A contributes to microenvironment-coordinated evasion of melanoma cells from dual BRAF/MEK inhibition and it might be a good candidate predictor of short-term benefit from dual BRAF/MEK inhibition.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-022-02354-w.

Prognostic and Immune Implications of a Novel Pyroptosis-Related Five-Gene Signature in Breast Cancer

Background

Breast cancer (BC) is the most common cancer among women worldwide, with enormous heterogeneity. Pyroptosis has a significant impact on the development and progression of tumors. Nonetheless, the possible correlation between pyroptosis-related genes (PRGs) and the BC immune microenvironment has yet to be investigated.

Materials and methods

In The Cancer Genome Atlas Breast Cancer cohort, 38 PRGs were shown to be significantly different between malignant and non-malignant breast tissues. The 38 PRGs’ consensus clustering grouped 1,089 individuals into two pyroptosis-related (PR) patterns. Using univariate and LASSO-Cox analyses, a PR five-gene predictive signature was constructed based on the differentially expressed genes between two clusters. The tools estimation of stromal and immune cells in malignant tumours using expression data (ESTIMATE), cell type identification by estimating relative subsets Of RNA transcripts (CIBERSORT), and single-sample gene set enrichment analysis (ssGSEA) were used to investigate the BC tumor microenvironment (TME).

Results

In TME, the two PR clusters displayed distinct clinicopathological characteristics, survival outcomes, and immunocyte infiltration features. The developed five-signature model (SEMA3B, IGKC, KLRB1, BIRC3, and PSME2) classified BC patients into two risk groups based on the estimated median risk score. Patients in the low-scoring category had a higher chance of survival and more extensive immunocyte infiltration. An external validation set can yield similar results.

Conclusion

Our data suggest that PRGs have a significant impact on the BC immunological microenvironment. The PR clusters and associated predictive signature stimulate additional research into pyroptosis in order to optimize therapeutic strategies for BC patients and their responses to immune therapy.

IL-2 Modulates TAMs Derived Exosomal MiRNAs to Ameliorate Hepatocellular Carcinoma Development and Progression

Background. Interleukin-2 (IL-2) is proved to play an irreplaceable role in antitumor regulation in numerous experimental and clinical trials. Tumor-associated macrophages (TAMs) are able to release exosomes to promote the development and progression of hepatocellular carcinoma (HCC) as essential component of microenvironment. In this study, our intention is to explore the effects of the exosomes from TAMs with IL-2 treatment on HCC development. TAMs were collected and cultured from HCC tissues. The exosomes from the TAMs treated with IL-2 (Exo^IL2-TAM) or not (Exo^TAM) were identified and used to treat HCC cells in vivo and in vitro. The proliferation, apoptosis, and metastasis of HCC cells were measured. The changes of miRNAs in exosomes were explored to clarify the possible mechanisms. Both decrease of cell proliferation and metastasis and increase of apoptosis were observed with Exo^IL2-TAM treatment compared with Exo^TAMin vivo and in vitro. miR-375 was obviously augmented in Exo^IL2-TAM and HCC cells treated with Exo^IL2-TAM. Taken together, IL-2 may modulate exosomal miRNAs from TAMs to ameliorate hepatocellular carcinoma development. This study provides a new perspective to explain the mechanism by which IL-2 inhibits hepatocellular carcinoma and implies the potential clinical value of exosomal miRNAs released by TAMs.

Advances in antigens associated with Idiopathic Membranous Nephropathy

Membranous nephropathy (MN) is a common cause of nephrotic syndrome in adults. Idiopathic MN (IMN), one of the forms of MN, usually has an unknown etiology. IMN is described as an autoimmune disease, and its pathogenesis is quite complex. The discovery of the M-type phospholipase A₂ receptor (PLA₂R) plays an important role in promoting our understanding of IMN, although the exact mechanisms of its occurrence and development are still not completely clear. Other target antigens have been discovered one after another, as considerable progress has been made in the molecular pathomechanisms of IMN. Here, we review the findings about the target antigens associated with IMN in recent years. It is hoped that this article can provide researchers with some scientific issues or innovative ideas for future studies of IMN, which will provide clinicians with more knowledge about further improving their abilities to provide better medical care for IMN patients.

New Angiogenic Regulators Produced by TAMs: Perspective for Targeting Tumor Angiogenesis

Simple Summary

Since the targeting of a single pro-angiogenic factor fails to improve oncological disease outcome, significant efforts have been made to identify new pro-angiogenic factors that could compensate for the deficiency of current therapy or act independently as single drugs. Our review aims to present the state-of-the art for well-known and recently described factors produced by macrophages that induce and regulate angiogenesis. A number of positive and negative regulators of angiogenesis in the tumor microenvironment are produced by tumor-associated macrophages (TAMs). Accumulating evidence has indicated that, apart from the well-known angiogenic factors, there are plenty of novel angiogenesis-regulating proteins that belong to different classes. We summarize the data regarding the direct or indirect mechanisms of the interaction of these factors with endothelial cells during angiogenesis. We highlight the recent findings that explain the limitations in the efficiency of current anti-angiogenic therapy approaches.

Abstract

Angiogenesis is crucial to the supply of a growing tumor with nutrition and oxygen. Inhibition of angiogenesis is one of the main treatment strategies for colorectal, lung, breast, renal, and other solid cancers. However, currently applied drugs that target VEGF or receptor tyrosine kinases have limited efficiency, which raises a question concerning the mechanism of patient resistance to the already developed drugs. Tumor-associated macrophages (TAMs) were identified in the animal tumor models as a key inducer of the angiogenic switch. TAMs represent a potent source not only for VEGF, but also for a number of other pro-angiogenic factors. Our review provides information about the activity of secreted regulators of angiogenesis produced by TAMs. They include members of SEMA and S100A families, chitinase-like proteins, osteopontin, and SPARC. The COX-2, Tie2, and other factors that control the pro-angiogenic activity of TAMs are also discussed. We highlight how these recent findings explain the limitations in the efficiency of current anti-angiogenic therapy. Additionally, we describe genetic and posttranscriptional mechanisms that control the expression of factors regulating angiogenesis. Finally, we present prospects for the complex targeting of the pro-angiogenic activity of TAMs.

Integrated Genome-Wide DNA Methylation and RNAseq Analysis of Hippocampal Specimens Identifies Potential Candidate Genes and Aberrant Signalling Pathways in Patients with Hippocampal Sclerosis

Background and Aims

DNA methylation and demethylation play a crucial role in the regulation of gene expression, though their interplay during pathogenesis of hippocampal scelerosis (HS) remains elusive. The present study was designed to investigate the DNA methylation regulated changes in expression of HS patients.

Methods

We performed integrative analysis of genome-wide CpG-DNA methylation profiling and RNA sequencing to profile global changes in promoter methylation and gene expression in HS patients. Real time PCR was performed to validate the findings of methylation and RNA sequencing.

Results

A total of 16040 sites showed altered DNA methylation in all the CpG islands. Of these, 3185 sites were in the promoter regions, of which 66 genes showed an inverse correlation between methylation and expression. These genes are largely related to pathways predicted to participate in axon guidance by semaphorins, MAPK, ionotropic glutamate receptor pathway, notch signaling, regulatory activities related to TFAP2A and immune response, with the most distinct ones included TFAP2A, NRP1, SEMA3B, CACNG2, MAP3K11, and ADAM17.

Conclusion

We performed integrated analysis of genomic methylation signature and differential gene expression patterns of hippocampal tissues resected from patients with HS for the first time. Collectively, our findings implicate DNA methylation as a critical regulator of the pathogenic mechanisms of epileptogenesis associated with HS.

Class-3 semaphorins: Potent multifunctional modulators for angiogenesis-associated diseases

Semaphorins, the neuronal guidance cues, were shown to have broad influences on pathophysiological processes such as bone remodeling, immune responses, and angiogenesis. In particular, Class-3 Semaphorins (SEMA3) is considered a vital regulator involved in angiogenesis. Scientific evidence has pointed to the role of angiogenesis in many diseases, and numerous efforts have been made to explore the possibilities of curing those diseases by targeting angiogenesis. Nevertheless, the efficacies are limited owing to the complex mechanisms of angiogenesis. Hence, investigating the mechanisms of SEMA3 in angiogenesis may contribute to novel therapeutics for diseases. Previous reviews mainly focused on the various functions of semaphorins in one particular disease, and the specific angiogenesis mechanism of SEMA3 in diverse diseases has not been well elucidated. Additionally, the role of SEMA3 in angiogenesis remains elusive, as contradicting results have been found in different disease types. Some evidence from recent studies implies that, while most SEMA3 molecules inhibit pathological angiogenesis in different diseases, occasionally SEMA3 may also promote angiogenesis. This review summarizes the specific role of SEMA3 in a variety of angiogenesis-associated diseases, and documents SEMA3 may be a promising therapeutic target for treating angiogenesis-associated diseases.

Semaphorins as emerging clinical biomarkers and therapeutic targets in cancer

Semaphorins are a large family of developmental regulatory signals, characterized by aberrant expression in human cancers. These molecules crucially control cell-cell communication, cell migration, invasion and metastasis, tumor angiogenesis, inflammatory and anti-cancer immune responses. Semaphorins comprise secreted and cell surface-exposed molecules and their receptors are mainly found in the Plexin and Neuropilin families, which are further implicated in a signaling network controlling the tumor microenvironment. Accumulating evidence indicates that semaphorins may be considered as novel clinical biomarkers for cancer, especially for the prediction of patient survival and responsiveness to therapy. Moreover, preclinical experimental studies have demonstrated that targeting semaphorin signaling can interfere with tumor growth and/or metastatic dissemination, suggesting their relevance as novel therapeutic targets in cancer; this has also prompted the development of semaphorin-interfering molecules for application in the clinic. Here we will survey, in diverse human cancers, the current knowledge about the relevance of semaphorin family members, and conceptualize potential lines of future research development in this field.

Construction of a 14-lncRNA risk score system predicting survival of children with acute myelocytic leukemia

Acute myelocytic leukemia (AML) is a frequent type of acute leukemia. The present study was performed to build a risk score system for the prognostic prediction of AML. AML RNA-sequencing data from samples from 111 children were downloaded from The Cancer Genome Atlas database. Using the DEseq and edgeR packages, the differentially expressed long non-coding RNAs (DE-lncRNAs) between bad and good prognosis groups were identified. A survival package was used to screen prognosis-associated lncRNAs and clinical factors. The optimal lncRNA combination was selected using the penalized package, and the risk-score system was built and evaluated. After the lncRNA-mRNA expression correlation network was constructed, the potential pathways involving the key lncRNAs were enriched using Gene Set Enrichment Analysis. Among the 61 DE-lncRNAs, 48 lncRNAs were significantly associated with prognosis. Relapse was an independent prognostic factor. The optimal 14-lncRNA risk score system was constructed. After 730 differentially expressed mRNAs were identified between the good and bad prognosis groups divided using a prognostic index, the lncRNA-mRNA expression correlation network was constructed. Enrichment analysis showed that semaphorin-3C [SEMA3C; regulated by probable leucine-tRNA ligase, mitochondrial (LARS2-AS1)] and secreted frizzled-related protein 5 [SFRP5; mediated by WASH complex subunit 5 (WASHC5)-antisense RNA 1 (AS1)] were involved in axon guidance and the Wnt signaling pathway, respectively. A 14-lncRNA (including paired box protein Pax8-AS1 and MYB AS1) risk-score system might be effective in predicting the prognosis of AML. Axon guidance (involving SEMA3C and LARS2-AS1) and the Wnt signaling pathway (involving SFRP5 and WASHC5-AS1) might be two important pathways affecting the prognosis of AML.

Loss of BAP1 expression is associated with an immunosuppressive microenvironment in uveal melanoma, with implications for immunotherapy development

Immunotherapy using immune checkpoint inhibitors (ICIs) induces durable responses in many metastatic cancers. Metastatic uveal melanoma (mUM), typically occurring in the liver, is one of the most refractory tumours to ICIs and has dismal outcomes. Monosomy 3 (M3), polysomy 8q, and BAP1 loss in primary uveal melanoma (pUM) are associated with poor prognoses. The presence of tumour-infiltrating lymphocytes (TILs) within pUM and surrounding mUM - and some evidence of clinical responses to adoptive TIL transfer - strongly suggests that UMs are indeed immunogenic despite their low mutational burden. The mechanisms that suppress TILs in pUM and mUM are unknown. We show that BAP1 loss is correlated with upregulation of several genes associated with suppressive immune responses, some of which build an immune suppressive axis, including HLA-DR, CD38, and CD74. Further, single-cell analysis of pUM by mass cytometry confirmed the expression of these and other markers revealing important functions of infiltrating immune cells in UM, most being regulatory CD8+ T lymphocytes and tumour-associated macrophages (TAMs). Transcriptomic analysis of hepatic mUM revealed similar immune profiles to pUM with BAP1 loss, including the expression of IDO1. At the protein level, we observed TAMs and TILs entrapped within peritumoural fibrotic areas surrounding mUM, with increased expression of IDO1, PD-L1, and β-catenin (CTNNB1), suggesting tumour-driven immune exclusion and hence the immunotherapy resistance. These findings aid the understanding of how the immune response is organised in BAP1 - mUM, which will further enable functional validation of detected biomarkers and the development of focused immunotherapeutic approaches. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Overexpression of Semaphorin 3A is a Marker Associated with Poor Prognosis in Patients with Nasopharyngeal Carcinoma

Semaphorins were discovered as guidance signals that mediate neural development. Recent studies suggest that semaphorin 3A (Sema3A), a member of the semaphorin family, is involved in the development of several cancers. This study aimed to analyze the association of Sema3A with the clinical features of nasopharyngeal carcinoma (NPC), an Epstein–Barr virus-associated carcinoma, and the Epstein–Barr virus primary oncogene latent membrane protein 1 (LMP1). The expression of Sema3A and LMP1 was immunohistochemically examined in the 35 NPC specimens. The mean expression scores for Sema3A and LMP1 were 20.8% ± 14.5% and 13.9% ± 14.8%, respectively. The expression of Sema3A significantly correlated with that of LMP1 (r = 0.41, p = 0.014). In addition, the Sema3A high cohort showed significantly poorer prognosis than the Sema3A low cohort. Sema3A expression was higher in the LMP1-positive KH-1 and KR-4 cell lines compared to the LMP1-negative HeLa cells. Overexpression of LMP1 in the LMP1-negative AdAH cell line upregulated Sema3A expression, both at the transcriptional and translational level. Finally, Sema3A expression was associated with poor prognosis in patients with NPC. Our data suggest that LMP1 induces the expression of Sema3A, which may promote tumor progression in NPC.

Semaphorins in Angiogenesis and Autoimmune Diseases: Therapeutic Targets?

The axonal guidance molecules, semaphorins, have been described to function both physiologically and pathologically outside of the nervous system. In this review, we focus on the vertebrate semaphorins found in classes 3 through 7 and their roles in vascular development and autoimmune diseases. Recent studies indicate that while some of these vertebrate semaphorins promote angiogenesis, others have an angiostatic function. Since some semaphorins are also expressed by different immune cells and are known to modulate immune responses, they have been implicated in autoimmune disorders such as multiple sclerosis, rheumatoid arthritis, systemic lupus erythematosus and systemic sclerosis. We conclude this review by addressing strategies targeting semaphorins as potential therapeutic agents for angiogenesis and autoimmune diseases.

Semaphorin 4C Promotes Macrophage Recruitment and Angiogenesis in Breast Cancer

Semaphorins are a large family of evolutionarily conserved morphogenetic molecules that are associated with repelling axonal guidance. Intriguingly, recent researches indicate that semaphorins are involved in cancer progression. Semaphorin 4C (SEMA4C) has long been considered a neuronal migration gene, but we detected that it is also highly expressed in many malignant human cancers. During an investigation of subcutaneous tumor models, we found that SEMA4C expression promoted tumor growth and progression. We discovered that SEMA4C was involved in maintaining tumor cell self-renewal, likely by regulating the p53 pathway. Inhibiting the expression of endogenous SEMA4C in tumor cells impaired growth and induced senescence and cell-cycle arrest in the G₂-phase. In addition, we found that SEMA4C induced the production of angiogenin and colony-stimulating factor-1 (CSF-1) in tumor cells by activating the NF-κB pathway in a plexinB2-dependent manner. In conclusion, SEMA4C expression in breast cancer cells promotes cancer cell proliferation, macrophage recruitment, and angiogenesis. Thus, inhibition of SEMA4C activity may be a novel therapeutic strategy for human breast cancer. IMPLICATIONS: In breast cancer, therapeutic targeting of the SEMA4C pathway may prevent tumor growth, angiogenesis, metastasis, and progression.

G protein-coupled receptor kinase 2 regulating β2-adrenergic receptor signaling in M2-polarized macrophages contributes to hepatocellular carcinoma progression

Background: β2-adrenoceptors (β2-ARs) are expressed on the surface of immune cells, including tumor-associated macrophages (TAMs). Previous studies have demonstrated that the expression of β2-ARs in hepatocellular carcinoma (HCC) is significantly increased in vitro. However, the role of β2-AR in M2-polarized macrophages remains unclear. G protein-coupled receptor kinase 2 (GRK2) can regulate G protein-coupled receptor (GPCR). Previous studies showed that down-regulation of GRK2 in HCC contributes the HCC progression, but it still remains unclear whether the regulation of β2-AR in M2-polarized macrophages by GRK2 can promote HCC.

Purpose: The present study was designed to investigate the role of activated β2-AR in M2-polarized macrophages in the HCC progression and GRK2 regulatory effect, as well as the underlying mechanisms involved.

Results: The results demonstrated that the M2-polarized macrophages were increased with HCC progression. In vitro, the activation of β2-AR by terbutaline in M2-polarized macrophages elevated the proliferative, migratory and invasive attributes of HCC cells. Furthermore, GRK2 down-regulation in β2-AR activated M2-polarized macrophages activated the downstream cyclic adenosine monophosphate (cAMP)/protein kinase A/cAMP-response element binding protein and cAMP/interleukin-6/signal transducer and the activator of transcription 3 signaling pathways, contributing to the secretion of tumor-associated cytokines, and thus resulting in the promotion of malignant biological behavior in HCC cells.

Conclusion: These findings suggest that the regulation of β2-AR occurs through the silencing of GRK2 in M2-polarized macrophages, which is conducive to HCC development, through its engagement in the activation of downstream signaling.

Expression of Semaphorin 3B (SEMA3B) in Various Grades of Endometrial Cancer

BACKGROUND SEMA3B is known as an inhibitor of angiogenesis and cell proliferation. During carcinogenesis, the loss of SEMA3B function is observed, which results in the progression of neoplastic changes. The aim of this study was to evaluate the expression profile of SEMA3B in endometrial cancer (G1-G3) in comparison to the control group and to assess whether the observed changes in expression could become a molecular marker in endometrial cancer. MATERIAL AND METHODS The study group consisted of 45 patients diagnosed with endometrial cancer (G1, 17; G2, 15; G3, 13). The control group included 15 patients. SEMA3B expression was assessed using the immunohistochemical method. Statistical analysis was carried out using the Statistica 12 PL program (StatSoft, USA). It included the Kruskal-Wallis test and post hoc Dunn's test (p<0.05). RESULTS Statistically significant differences in the level of SEMA3B expression were observed between all analyzed groups. The expression pattern of SEMA3B was as follows: cancer cells G1>G2>G3; endothelial cells: G3>G1>G2; stromal cells: G2>G1>G3. CONCLUSIONS Analysis of the SEMA3B expression profile shows the complexity of neoplastic transformation, which confirms the different expression of SEMA3B in endometrial cancer cells and endothelial cells. The present results and data in the literature data suggest that SEMA3B expression indicates the progression of carcinogenesis in the context of endometrial cancer.

Class-3 Semaphorins and Their Receptors: Potent Multifunctional Modulators of Tumor Progression

Semaphorins are the products of a large gene family containing 28 genes of which 21 are found in vertebrates. Class-3 semaphorins constitute a subfamily of seven vertebrate semaphorins which differ from the other vertebrate semaphorins in that they are the only secreted semaphorins and are distinguished from other semaphorins by the presence of a basic domain at their C termini. Class-3 semaphorins were initially characterized as axon guidance factors, but have subsequently been found to regulate immune responses, angiogenesis, lymphangiogenesis, and a variety of additional physiological and developmental functions. Most class-3 semaphorins transduce their signals by binding to receptors belonging to the neuropilin family which subsequently associate with receptors of the plexin family to form functional class-3 semaphorin receptors. Recent evidence suggests that class-3 semaphorins also fulfill important regulatory roles in multiple forms of cancer. Several class-3 semaphorins function as endogenous inhibitors of tumor angiogenesis. Others were found to inhibit tumor metastasis by inhibition of tumor lymphangiogenesis, by direct effects on the behavior of tumor cells, or by modulation of immune responses. Notably, some semaphorins such as sema3C and sema3E have also been found to potentiate tumor progression using various mechanisms. This review focuses on the roles of the different class-3 semaphorins in tumor progression.

Neuroproteins in Cancer: Assumed Bystanders Become Culprits

Recent breakthrough discoveries have highlighted the stimulatory role of nerves in cancer initiation and progression, through the release of neurotransmitters and growth factors by nerve terminals in the tumor microenvironment. Intriguingly, neuroproteins such as neuronal membrane proteins, synaptic proteins, neurotransmitters, and neurotrophic growth factors as well as their corresponding receptors, to name only a few, are frequently found in proteomic analyses of cancer tissues external to the brain and central nervous system. While the usual explanation was that neuroproteins were actually not specific to the nervous system and were therefore also expressed in cancer cells, it now appears that the presence of neuroproteins in cancer is largely due to the infiltration of nerves in the tumor microenvironment. Given the newly identified function of nerves as promoters of cancer growth and metastasis, neuroproteins should be considered with great attention because they may actually represent innovative biomarkers and therapeutic targets in oncology.

Characterization of a novel OTX2-driven stem cell program in Group 3 and Group 4 medulloblastoma

Medulloblastoma (MB) is the most common malignant primary pediatric brain cancer. Among the most aggressive subtypes, Group 3 and Group 4 originate from stem/progenitor cells, frequently metastasize, and often display the worst prognosis, yet we know the least about the molecular mechanisms driving their progression. Here, we show that the transcription factor orthodenticle homeobox 2 (OTX2) promotes self-renewal while inhibiting differentiation in vitro and increases tumor initiation from MB stem/progenitor cells in vivo. To determine how OTX2 contributes to these processes, we employed complementary bioinformatic approaches to characterize the OTX2 regulatory network and identified novel relationships between OTX2 and genes associated with neuronal differentiation and axon guidance signaling in Group 3 and Group 4 MB stem/progenitor cells. In particular, OTX2 levels were negatively correlated with semaphorin (SEMA) signaling, as expression of 9 SEMA pathway genes is upregulated following OTX2 knockdown with some being potential direct OTX2 targets. Importantly, this negative correlation was also observed in patient samples, with lower expression of SEMA4D associated with poor outcome specifically in Group 4 tumors. Functional proof-of-principle studies demonstrated that increased levels of select SEMA pathway genes are associated with decreased self-renewal and growth in vitro and in vivo and that RHO signaling, known to mediate the effects of SEMA genes, is contributing to the OTX2 KD phenotype. Our study provides mechanistic insight into the networks controlled by OTX2 in MB stem/progenitor cells and reveals novel roles for axon guidance genes and their downstream effectors as putative tumor suppressors in MB.

Impact of neutrophil to lymphocyte ratio on survival for hepatocellular carcinoma after curative resection

BACKGROUND

Neutrophil-lymphocyte ratio (NLR) represents a pro-tumor inflammatory environment and host immunity. The aim of this study was to examine the effect of subsequent NLR for hepatocellular carcinoma (HCC) after liver resection.

METHODS

A total of 672 patients had liver resection for HCC were included in this study. NLR at diagnosis of HCC and HCC recurrence were collected. NLR at 2.5 was used as cut-off value to calculate its prognostic effect.

RESULTS

According to NLR cut-off value, the patients with NLR >2.5 had larger tumor size, higher histology grade, and higher rates of tumor multiplicity and vascular invasion. After a median follow-up of 76.3 months, 437 (65.0%) patients had tumor recurrence. The 1-, 3- and 5-year recurrence-free survival were 77.4%, 55.2% and 44.8% in NLR ≤2.5 group, compared to 64.1%, 45.2% and 35.5% in NLR >2.5 group (P = 0.016). When patients had tumor recurrence, 5-year post-recurrent survival was best in the patients staying with NLR ≤2.5 all the time and decreased from 45.9% to 24.6% if NLR was ≤2.5 at resection and became >2.5 at recurrence (P = 0.013).

CONCLUSION

High NLR was an independent unfavorable prognostic factor. Subsequent change of NLR between liver resection and HCC recurrence could predict post-recurrent survival.

Shear stress-regulated miR-27b controls pericyte recruitment by repressing SEMA6A and SEMA6D

AIMS

Vessel maturation involves the recruitment of mural cells such as pericytes and smooth muscle cells. Laminar shear stress is a major trigger for vessel maturation, but the molecular mechanisms by which shear stress affects recruitment of pericytes are unclear. MicroRNAs (miRs) are small non-coding RNAs, which post-transcriptionally control gene expression. The aim of the present study was to unveil the mechanism by which shear stress-regulated microRNAs contribute to vessel maturation.

METHODS AND RESULTS

Here, we show that laminar shear stress increased miR-27a and miR-27b expression in vitro and in ex vivo in mouse femoral artery explants. Overexpression of miR-27b in endothelial cells increased pericyte adhesion and pericyte recruitment in vitro. In vitro barrier function of endothelial-pericyte co-cultures was augmented by miR-27b overexpression, whereas inhibition of miR-27a/b reduced adhesion and pericyte coverage and decreased barrier functions. In vivo, pharmacological inhibition of miR-27a/b by locked nucleic acid antisense oligonucleotides significantly reduced pericyte coverage and increased water content in the murine uterus. MiR-27b overexpression repressed semaphorins (SEMA), which mediate repulsive signals, and the vessel destabilizing human but not mouse Angiopoietin-2 (Ang-2). Silencing of SEMA6A and SEMA6D rescued the reduced pericyte adhesion by miR-27 inhibition. Furthermore, inhibition of SEMA6D increased barrier function of an endothelial-pericyte co-culture in vitro.

CONCLUSION

The present study demonstrates for the first time that shear stress-regulated miR-27b promotes the interaction of endothelial cells with pericytes, partly by repressing SEMA6A and SEMA6D.

Nerve Dependence: From Regeneration to Cancer

Nerve dependence has long been described in animal regeneration, where the outgrowth of axons is necessary to the reconstitution of lost body parts and tissue remodeling in various species. Recent discoveries have demonstrated that denervation can suppress tumor growth and metastasis, pointing to nerve dependence in cancer. Regeneration and cancer share similarities in regard to the stimulatory role of nerves, and there are indications that the stem cell compartment is a preferred target of innervation. Thus, the neurobiology of cancer is an emerging discipline that opens new perspectives in oncology.

Inflammation and Cancer: Extra- and Intracellular Determinants of Tumor-Associated Macrophages as Tumor Promoters

One of the hallmarks of cancer-related inflammation is the recruitment of monocyte-macrophage lineage cells to the tumor microenvironment. These tumor infiltrating myeloid cells are educated by the tumor milieu, rich in cancer cells and stroma components, to exert functions such as promotion of tumor growth, immunosuppression, angiogenesis, and cancer cell dissemination. Our review highlights the ontogenetic diversity of tumor-associated macrophages (TAMs) and describes their main phenotypic markers. We cover fundamental molecular players in the tumor microenvironment including extra- (CCL2, CSF-1, CXCL12, IL-4, IL-13, semaphorins, WNT5A, and WNT7B) and intracellular signals. We discuss how these factors converge on intracellular determinants (STAT3, STAT6, STAT1, NF-κB, RORC1, and HIF-1α) of cell functions and drive the recruitment and polarization of TAMs. Since microRNAs (miRNAs) modulate macrophage polarization key miRNAs (miR-146a, miR-155, miR-125a, miR-511, and miR-223) are also discussed in the context of the inflammatory myeloid tumor compartment. Accumulating evidence suggests that high TAM infiltration correlates with disease progression and overall poor survival of cancer patients. Identification of molecular targets to develop new therapeutic interventions targeting these harmful tumor infiltrating myeloid cells is emerging nowadays.

Experimental Approaches for Studying Semaphorin Signals in Tumor Growth and Metastasis in Mouse Models

Tumor growth and metastatic dissemination are complex multistep processes. They clearly depend on the intrinsic behavior of cancer cells, but are remarkably influenced by a variety of stromal cells present in the tumor microenvironment, which include those implicated in tumor angiogenesis, as well as bone marrow-derived cells recruited from the circulation. Moreover, multiple molecular signals exchanged between cancer cells and non-neoplastic stromal cells control tumor growth and metastasis; notably, members of the semaphorin family are emerging players in this scenario.In vivo tumor models represent the best setting for studying metastatic tumor progression, as they allow recapitulating the contribution of multiple cell types and signaling molecules in a complex tissue context, subject to pathophysiological local and systemic responses, such as metabolic changes, hypoxia, necrosis, fibrosis, inflammation, and cytokine release. Here, we describe some experimental approaches based on murine models to study the role of semaphorin signaling in tumor growth and metastatic progression in vivo.

The role of the semaphorins in cancer

The semaphorins were initially characterized as axon guidance factors, but have subsequently been implicated also in the regulation of immune responses, angiogenesis, organ formation, and a variety of additional physiological and developmental functions. The semaphorin family contains more then 20 genes divided into 7 subfamilies, all of which contain the signature sema domain. The semaphorins transduce signals by binding to receptors belonging to the neuropilin or plexin families. Additional receptors which form complexes with these primary semaphorin receptors are also frequently involved in semaphorin signaling. Recent evidence suggests that semaphorins also fulfill important roles in the etiology of multiple forms of cancer. Some semaphorins have been found to function as bona-fide tumor suppressors and to inhibit tumor progression by various mechanisms while other semaphorins function as inducers and promoters of tumor progression.

SEMA3B improves the survival of patients with esophageal squamous cell carcinoma by upregulating p53 and p21

As one of the most common malignancies, esophageal squamous cell carcinoma (ESCC) is ranked as the sixth leading cause of cancer-related death worldwide. In our previous study, by employing cDNA microarray analysis, semaphorin 3B (SEMA3B) was found to be significantly downregulated in ESCC. In the present study, SEMA3B downregulation at the mRNA level was found in 34 of 60 primary ESCCs (56.7%) and in 6 of 9 ESCC cell lines (66.7%) by transcription-polymerase chain reaction (RT-PCR). Moreover, immunohistochemical (IHC) staining of SEMA3B in a tissue microarray further indicated that downregulated expression of SEMA3B protein was found in 125 of 222 (56.3%) ESCC cases and downregulation of SEMA3B protein was significantly correlated with lymph node metastasis (P=0.000), advanced clinicopathological stage (P=0.001) and poor disease-specific survival (P=0.017) of ESCC patients. In addition, functional studies demonstrated that the SEMA3B gene could suppress the tumorigenic ability of ESCC cells and cell motility. Furthermore, it was found that by upregulating p53 and p21 expression and inhibiting Akt (Ser473) phosphorylation, SEMA3B could induce cell cycle arrest at G1/S phase. Taken together, our results suggest that SEMA3B may be an important tumor-suppressor gene in the malignant progression of ESCC, as well as a valuable prognostic marker for ESCC patients.

Vitamin D Deficiency Is Associated With Increased Risk of Non-alcoholic Steatohepatitis in Adults With Non-alcoholic Fatty Liver Disease: Possible Role for MAPK and NF-κB?

OBJECTIVES

The objective of this study was to determine the relationship of serum vitamin D deficiency (VDD) to histologic features of non-alcoholic fatty liver disease (NAFLD), and associated demographic, clinical, laboratory, and transcriptomic data in the well-characterized Non-alcoholic Steatohepatitis Clinical Research Network (NASH CRN) cohort.

METHODS

Serum vitamin D 25(OH)D (VD) was quantified by liquid chromatography-tandem mass spectrometry in 190 adults (>18 years) with biopsy-proven NAFLD. Subjects were categorized according to their level of VD as either sufficient (>30 ng/ml), insufficient (≥20≤30 ng/ml), or deficient (VDD; <20 ng/ml). Multivariable logistic regression was used to investigate the association of VDD and the presence of definite NASH and individual histological features of NAFLD after adjusting for age, sex, race, body mass index, alanine aminotransferase, and diabetes status. Hepatic transcriptomic data was compared between VDD and non-VDD subjects.

RESULTS

VDD was present in 55% of subjects and was independently associated with definitive NASH (odds ratio (OR) 3.15, 95% confidence interval (CI), 1.62-6.15, P=0.001), increased lobular inflammation (OR=1.98, 95% CI, 1.08-3.61, P=0.026), more ballooning (OR=2.38, 95% CI, 1.32-4.30, P=0.004), and the presence of fibrosis (OR=2.32, 95% CI, 1.13-4.77, P=0.022). There was a significant inverse relationship between lower levels of serum resistin and increased VD level category (P=0.013). The KRT10, SEMA3B, SNORD3C, ARSD, and IGKV4-1 genes were differentially expressed (false discovery rate <0.05) between VDD and non-VDD subjects. Gene ontology and pathway analysis suggest activation of the mitogen-activated protein kinase and nuclear factor-κB pathways in VDD NAFLD subjects.

CONCLUSIONS

VDD is prevalent among US adult NAFLD patients and is independently associated with a definitive diagnosis of NASH and increased histological severity. Novel associations in proinflammatory pathways were identified, which suggest the mechanism for VDD in the pathogenesis of NASH and support dietary and/or lifestyle modifications to increase vitamin D levels in these patients.

Identification of Recurrence-Related microRNAs from Bone Marrow in Hepatocellular Carcinoma Patients

Hepatocellular carcinoma (HCC) is a poor-prognosis cancer due to its high rate of recurrence. microRNAs (miRNAs) are a class of small non-coding RNA molecules that affect crucial processes in cancer development. The objective of this study is to identify the role of miRNAs in patient bone marrow (BM) and explore the function of these molecules during HCC progression. We purified miRNAs from bone marrow cells of seven HCC patients, and divided them into three fractions by cell surface markers as follows: CD14(+) (macrophage), CD14(-)/CD45(+) (lymphocyte), and CD14(-)/CD45(-)/EpCAM(+) (epithelial cell). We employed microarray-based profiling to analyze miRNA expression in the bone marrow of patients with HCC. Differentially expressed miRNAs were significantly different between fractions from whole bone marrow, macrophages, and lymphocytes, and depended on stages in tumor progression. Differences in expression of miRNAs associated with cell proliferation also varied significantly between HCC patients with recurrence, multiple tumors, and advanced clinical stages. These results suggest that miRNA profiles in separated fractions of BM cells are associated with HCC progression.

Tumor Suppressor Function of the SEMA3B Gene in Human Lung and Renal Cancers

The SEMA3B gene is located in the 3p21.3 LUCA region, which is frequently affected in different types of cancer. The objective of our study was to expand our knowledge of the SEMA3B gene as a tumor suppressor and the mechanisms of its inactivation. In this study, several experimental approaches were used: tumor growth analyses and apoptosis assays in vitro and in SCID mice, expression and methylation assays and other. With the use of the small cell lung cancer cell line U2020 we confirmed the function of SEMA3B as a tumor suppressor, and showed that the suppression can be realized through the induction of apoptosis and, possibly, associated with the inhibition of angiogenesis. In addition, for the first time, high methylation frequencies have been observed in both intronic (32-39%) and promoter (44-52%) CpG-islands in 38 non-small cell lung carcinomas, including 16 squamous cell carcinomas (SCC) and 22 adenocarcinomas (ADC), and in 83 clear cell renal cell carcinomas (ccRCC). Correlations between the methylation frequencies of the promoter and the intronic CpG-islands of SEMA3B with tumor stage and grade have been revealed for SCC, ADC and ccRCC. The association between the decrease of the SEMA3B mRNA level and hypermethylation of the promoter and the intronic CpG-islands has been estimated in renal primary tumors (P < 0.01). Using qPCR, we observed on the average 10- and 14-fold decrease of the SEMA3B mRNA level in SCC and ADC, respectively, and a 4-fold decrease in ccRCC. The frequency of this effect was high in both lung (92-95%) and renal (84%) tumor samples. Moreover, we showed a clear difference (P < 0.05) of the SEMA3B relative mRNA levels in ADC with and without lymph node metastases. We conclude that aberrant expression and methylation of SEMA3B could be suggested as markers of lung and renal cancer progression.

Decreased semaphorin 3A expression is associated with a poor prognosis in patients with epithelial ovarian carcinoma

Semaphorin 3A (SEMA3A) was initially identified to play an important role in axonal guidance. Recently, SEMA3A has also been considered as a candidate tumor suppressor, since it is often downregulated in numerous types of cancer, including prostate cancer, breast cancer and glioma. However, the biological role of SEMA3A in ovarian cancer is not clear. In the present study, the expression of SEMA3A in ovarian cancer and normal ovarian epithelial tissues was detected by immunofluorescence, reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and western blotting, and the associations between the expression of SEMA3A with the development of ovarian cancer, clinicopathological characteristics and survival were also analyzed. Results from immunofluorescence, RT‑qPCR and western blotting showed that SEMA3A is significantly downregulated in epithelial ovarian carcinoma compared to normal ovarian epithelial specimens (P<0.05). The expression levels of SEMA3A were lower in the cancer tissues with III/IV stage [the International Federation of Gynecology and Obstetrics (FIGO) stage], poor histological grade, lymph node metastasis and distant metastasis compared to that in the cancer tissues with I/II stage (FIGO), well histological grade, or without lymph node metastasis and distant metastasis (P<0.05). A decreased expression of SEMA3A is associated with a poor prognosis (P<0.001). The present findings suggest that decreased SEMA3A expression may be associated with the development of epithelial ovarian carcinoma, and therefore, SEMA3A may be a valuable prognostic marker, as well as a potential molecular therapy target for ovarian cancer patients.

The role of the cell-cell interactions in cancer progression

In the field of cancer research, scientific investigations are based on analysing differences in the secretome, the proteome, the transcriptome, the expression of cell surface molecules, and the deregulation of signal transduction pathways between neoplastic and normal cells. Accumulating evidence indicates a crucial role in carcinogenesis concerning not only stromal cells but also normal cells from target organs and tissue where tumours emerge. The tumour microenvironment (TME) definitively plays an important role in regulating neighbouring cell behaviour. To date, limited attention has been focused upon interactions between cancer cells and normal cells. This review concentrates on the interactions between stromal and healthy cells from the TME in cancer development. In the article, the authors also describe mutations, genes and proteins expression pattern that are involved in tumour development in target organ.

A perspective on the role of class III semaphorin signaling in central nervous system trauma

Traumatic injury of the central nervous system (CNS) has severe impact on the patients’ quality of life and initiates many molecular and cellular changes at the site of insult. Traumatic CNS injury results in direct damage of the axons of CNS neurons, loss of myelin sheaths, destruction of the surrounding vascular architecture and initiation of an immune response. Class III semaphorins (SEMA3s) are present in the neural scar and influence a wide range of molecules and cell types in and surrounding the injured tissue. SEMA3s and their receptors, neuropilins (NRPs) and plexins (PLXNs) were initially studied because of their involvement in repulsive axon guidance. To date, SEMA3 signaling is recognized to be of crucial importance for re-vascularization, the immune response and remyelination. The purpose of this review is to summarize and discuss how SEMA3s modulate these processes that are all crucial components of the tissue response to injury. Most of the functions for SEMA3s are achieved through their binding partners NRPs, which are also co-receptors for a variety of other molecules implicated in the above processes. The most notable ligands are members of the vascular endothelial growth factor (VEGF) family and the transforming growth factor family. Therefore, a second aim is to highlight the overlapping or competing signaling pathways that are mediated through NRPs in the same processes. In conclusion, we show that the role of SEMA3s goes beyond inhibiting axonal regeneration, since they are also critical modulators of re-vascularization, the immune response and re-myelination.

The emerging role of class-3 semaphorins and their neuropilin receptors in oncology

The semaphorins, discovered over 20 years ago, are a large family of secreted or transmembrane and glycophosphatidylinositol -anchored proteins initially identified as axon guidance molecules crucial for the development of the nervous system. It has now been established that they also play important roles in organ development and function, especially involving the immune, respiratory, and cardiovascular systems, and in pathological disorders, including cancer. During tumor progression, semaphorins can have both pro- and anti-tumor functions, and this has created complexities in our understanding of these systems. Semaphorins may affect tumor growth and metastases by directly targeting tumor cells, as well as indirectly by interacting with and influencing cells from the micro-environment and vasculature. Mechanistically, semaphorins, through binding to their receptors, neuropilins and plexins, affect pathways involved in cell adhesion, migration, invasion, proliferation, and survival. Importantly, neuropilins also act as co-receptors for several growth factors and enhance their signaling activities, while class 3 semaphorins may interfere with this. In this review, we focus on the secreted class 3 semaphorins and their neuropilin co-receptors in cancer, including aspects of their signaling that may be clinically relevant.

Assay development for the discovery of semaphorin 3B inducing agents from natural product sources

Semaphorins are a class of membrane-bound and secreted proteins. They have been found to regulate basic cell functions such as axonal growth cone guidance and recent studies have focused on their effect on tumor progression. Semaphorin 3B (Sema3B) particularly is a secreted protein that has been known to modulate proliferation and apoptosis, processes that are critical for tumor progression and development. In spite of its importance, there is yet no high-throughput screening assay available to detect or quantify the expression of Sema3B for natural product anticancer drug discovery purposes. Therefore, the development of a new high-throughput bioassay for the discovery of Sema3B inducing agents from natural product sources is described herein. A wide variety of pure compounds and extracts from plants and microorganisms has been found suitable for screening using this Sema3B assay to detect and quantify the effect of Sema3B inducing agents and thereby identify new selective bioactive Sema3B lead compounds for anticancer drug discovery and development. Also, this new bioassay procedure is based on a high-throughput platform using an enzyme-linked immunosorbent assay that involves the optimization of sensitivity and selectivity levels as well as accuracy, reproducibility, robustness, and cost effectiveness.

Decreased expression of SEMA3A is associated with poor prognosis in gastric carcinoma

BACKGROUND/PURPOSE

SEMA3A (semaphorin-3A), is a secreted protein that belongs to the semaphorin family and can function as both a chemoattractive agent or a chemorepulsive agent. SEMA3A has been shown to be a tumor suppressor in various cancers. This study investigated the expression of SEMA3A in gastric cancer and its prognostic value for gastric cancer patients.

METHODS

We examined the expression of SEMA3A in paired cancerous and matched adjacent noncancerous gastric mucosa tissues by real-time quantitative RT-PCR (qRT-PCR) and western blotting. In vitro, we evaluate the effects of SEMA3A on gastric cancer cell proliferation and migration by MTT, transwell and wound-healing assays. Furthermore, we analyzed SEMA3A expression in 128 patients who underwent resection procedures using immunohistochemistry. The relationships between the SEMA3A expression levels, the clinicopathological factors, and patient survival were investigated.

RESULTS

Our results revealed decreased SEMA3A mRNA (P = 0.0037) and protein (P = 0.033) expression in tumor tissue samples compared with matched adjacent non-tumorous tissue samples. Overexpression of SEMA3A inhibits gastric cancer cell proliferation and migration in vitro. Immunohistochemical staining data showed that SEMA3A expression was significantly decreased in 54.68% of gastric cancer cases. In addition, the chi-square test revealed that low SEMA3A expression was significantly correlated with poor differentiation (P = 0.015), Vascular invasion (P = 0.001), depth of invasion (P < 0.001), lymph node metastasis (P = 0.029), distant metastasis (P = 0.002) and advanced TNM stage (P = 0.003). SEMA3A expression was positively correlated with clinical TNM stage, that suggested the more advanced clinical TNM stage corresponding to the lower expression level of SEMA3A (rs = -0.322, P < 0.001) by Spearman rank correlation analysis. Kaplan-Meier survival analysis demonstrated that low expression of SEMA3A was significantly correlated with a poor prognosis for gastric cancer patients (P < 0.001). The multivariate analysis revealed that SEMA3A expression was an independent prognostic factor of the overall survival rate of patients with gastric cancer.

CONCLUSION

SEMA3A expression decreased significantly as gastric cancer progressed and metastasized, suggesting that SEMA3A might serve as a candidate tumor suppressor and a potential prognostic biomarker in gastric carcinogenesis.

Anti-proliferative activity of 25-hydroxyvitamin D3 in human prostate cells

1α-Hydroxylation of 25-hydroxyvitamin D3 is believed to be essential for its biological effects. In this study, we evaluated the biological activity of 25(OH)D3 itself comparing with the effect of cell-derived 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3). First, we measured the cell-derived 1α,25(OH)2D3 level in immortalized human prostate cell (PZ-HPV-7) using [(3)H]-25(OH)D3. The effects of the cell-derived 1α,25(OH)2D3 on vitamin D3 24-hydroxylase (CYP24A1) mRNA level and the cell growth inhibition were significantly lower than the effects of 25(OH)D3 itself added to cell culture. 25-Hydroxyvitamin D3 1α-hydroxylase (CYP27B1) gene knockdown had no significant effects on the 25(OH)D3-dependent effects, whereas vitamin D receptor (VDR) gene knockdown resulted in a significant decrease in the 25(OH)D3-dependent effects. These results strongly suggest that 25(OH)D3 can directly bind to VDR and exerts its biological functions. DNA microarray and real-time RT-PCR analyses suggest that semaphorin 3B, cystatin E/M, and cystatin D may be involved in the antiproliferative effect of 25(OH)D3.

Tumor associated macrophages and neutrophils in tumor progression

Tumor-associated macrophages (TAMs) are a key component of the tumor microenvironment and orchestrate various aspects of cancer. Diversity and plasticity are hallmarks of cells of the monocyte-macrophage lineage. In response to distinct signals macrophages undergo M1 (classical) or M2 (alternative) activation, which represent extremes of a continuum in a spectrum of activation states. Metabolic adaptation is a key component of macrophage plasticity and polarization, instrumental to their function in homeostasis, immunity and inflammation. Generally, TAMs acquire an M2-like phenotype that plays important roles in many aspects of tumor growth and progression. There is now evidence that also neutrophils can be driven towards distinct phenotypes in response to microenvironmental signals. The identification of mechanisms and molecules associated with macrophage and neutrophil plasticity and polarized activation provides a basis for new diagnostic and therapeutic strategies.

Preoperative neutrophil-to-lymphocyte ratio is a predictor of survival after hepatectomy for hepatocellular carcinoma: a retrospective analysis

OBJECTIVE

To clarify the prognostic value of the preoperative blood neutrophil-to-lymphocyte ratio (NLR) in patients undergoing hepatectomy for hepatocellular carcinoma (HCC).

BACKGROUND

Although a high NLR has been reported to be a predictor of poor survival in patients with various cancers, it has not been extensively examined in patients with HCC.

METHODS

This retrospective study enrolled 958 patients who underwent hepatectomy without preoperative therapy for HCC from 1996 to 2009. Clinicopathological parameters, including NLR, were evaluated to identify predictors of overall and recurrence-free survival after hepatectomy. Univariate and multivariate analyses were performed, using the Cox proportional hazards model. The best cutoff was determined with time-dependent receiver operating characteristic curve. To determine the mechanism of NLR elevation, immunohistological examination using CD163 staining was performed in 150 patients.

RESULTS

Univariate and multivariate analyses showed that NLR was an independent prognostic factor in overall and recurrence-free survival. The best cutoff of NLR was 2.81, and 238 of 958 patients (24.8%) had NLR of more than 2.81. The 5-year survival rate after hepatectomy was 72.9% in patients with NLR less than 2.81 and 51.5% in those with NLR 2.81 or more (P < 0.0001). CD163-positive cell counts were significantly higher in tumors in the group with NLR 2.81 or more than in the group with NLR less than 2.81 (P = 0.0004).

CONCLUSIONS

Our results show that NLR is an independent predictor of survival after hepatectomy in patients with HCC. Accumulation of tumor-associated macrophages in the tumor is associated with a high NLR.

Semaphorins in cancer: biological mechanisms and therapeutic approaches

The hallmarks of cancer include multiple alterations in the physiological processes occurring in normal tissues, such as cell proliferation, apoptosis, and restricted cell migration. These aberrant behaviors are due to genetic and epigenetic changes that affect signaling pathways controlling cancer cells, as well as the surrounding "normal" cells in the tumor microenvironment. Semaphorins and their receptors (mainly plexins and neuropilins) are aberrantly expressed in human tumors, and multiple family members are emerging as pivotal signals deregulated in cancer. Notably, different semaphorins can promote or inhibit tumor progression, depending on the implicated receptor complexes and responsive cell type. The important role of semaphorin signals in the regulation of tumor angiogenesis, invasion and metastasis has initiated multiple experimental approaches aimed at targeting these pathways to inhibit cancer.

The role of semaphorins and their receptors in vascular development and cancer

Semaphorins (Semas) are a large family of traditional axon guidance molecules. Through interactions with their receptors, Plexins and Neuropilins, Semas play critical roles in a continuously growing list of diverse biological systems. In this review, we focus on their function in regulating vascular development. In addition, over the past few years a number of findings have shown the crucial role that Semas and their receptors play in the regulation of cancer progression and tumor angiogenesis. In particular, Semas control tumor progression by directly influencing the behavior of cancer cells or, indirectly, by modulating angiogenesis and the function of other cell types in the tumor microenvironment (i.e., inflammatory cells and fibroblasts). Some Semas can activate or inhibit tumor progression and angiogenesis, while others may have the opposite effect depending on specific post-translational modifications. Here we will also discuss the diverse biological effects of Semas and their receptor complexes on cancer progression as well as their impact on the tumor microenvironment.

Class 3 semaphorins: physiological vascular normalizing agents for anti-cancer therapy

Findings from preclinical and clinical studies show that vascular normalization represents a novel strategy to enhance the efficacy of and overcome the acquired resistance to anti-angiogenic therapies in cancer. Several mechanisms of tumour vessel normalization have been revealed. Amongst them, secreted class 3 semaphorins (Sema3), which regulate axon guidance and angiogenesis, have been recently identified as novel vascular normalizing agents that inhibit metastatic dissemination by restoring vascular function. Here, we discuss the different biological functions and mechanisms of action of Sema3 in the context of tumour vascular normalization, and their impact on the different cellular components of the tumour microenvironment.