The potential of class 3 semaphorins as both targets and therapeutics in cancer

An Overview of the Molecular Cues and Their Intracellular Signaling Shared by Cancer and the Nervous System: From Neurotransmitters to Synaptic Proteins, Anatomy of an All-Inclusive Cooperation

We propose an overview of the molecular cues and their intracellular signaling involved in the crosstalk between cancer and the nervous system. While "cancer neuroscience" as a field is still in its infancy, the relation between cancer and the nervous system has been known for a long time, and a huge body of experimental data provides evidence that tumor-nervous system connections are widespread. They encompass different mechanisms at different tumor progression steps, are multifaceted, and display some intriguing analogies with the nervous system's physiological processes. Overall, we can say that many of the paradigmatic "hallmarks of cancer" depicted by Weinberg and Hanahan are affected by the nervous system in a variety of manners.

SEMA3C Promotes Cervical Cancer Growth and Is Associated With Poor Prognosis

Introduction: Aberrant activation of Semaphorin3C(SEMA3C) is widespread in human cancers. We aimed to analyze SEMA3C expression in cervical cancer and investigate the role of SEMA3C in cervical cancer and its underlying mechanism, which is important for exploring new therapeutic targets and prognostic factors.

Materials and Methods: The expression of SEMA3C was examined in paraffin-embedded cervical cancer specimens. In vivo and in vitro assays were performed to validate the effect of SEMA3C on cervical cancer cell proliferation and p-ERK pathway activation. Gene Set Enrichment Analysis (GSEA) was performed using The Cancer Genome Atlas (TCGA) data set.

Results: SEMA3C expression was associated with poor survival in both the TCGA cohort and our cohort. Silencing of SEMA3C suppressed cervical cancer cell proliferation, colony formation ability, and the activation of the p-ERK signaling pathway in vitro. SEMA3C depletion inhibited tumor growth in vitro. GSEA also showed that the epithelial mesenchymal transition (EMT), TGFβ signaling pathway, angiogenesis, and extracellular matrix (ECM) receptor interactions are associated with a high SEMA3C expression phenotype.

Conclusion: SEMA3C is correlated with poor prognosis of cervical cancer patients and promotes tumor growth via the activation of the p-ERK pathway.

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.

Role of Semaphorins in Immunopathologies and Rheumatic Diseases

Rheumatic diseases are disorders characterized by joint inflammation, in which other organs are also affected. There are more than two hundred rheumatic diseases, the most studied so far are rheumatoid arthritis, osteoarthritis, spondyloarthritis, systemic lupus erythematosus, and systemic sclerosis. The semaphorin family is a large group of proteins initially described as axon guidance molecules involved in nervous system development. Studies have demonstrated that semaphorins play a role in other processes such as the regulation of immunity, angiogenesis, bone remodeling, apoptosis, and cell migration and invasion. Moreover, semaphorins have been related to the pathogenesis of multiple sclerosis, asthma, Alzheimer, myocarditis, atherosclerosis, fibrotic diseases, osteopetrosis, and cancer. The aim of this review is to summarize current knowledge regarding the role of semaphorins in rheumatic diseases, and discuss their potential applications as therapeutic targets to treat these disorders.

Impact of semaphorin expression on prognostic characteristics in breast cancer

Breast cancer is one of the major causes of cancer-related deaths among women worldwide. Aberrant regulation of various growth factors, cytokines, and other proteins and their receptors in cancer cells drives the activation of various oncogenic signaling pathways that lead to cancer progression. Semaphorins are a class of proteins which are differentially expressed in various types of cancer including breast cancer. Earlier, these proteins were known to have a major function in the nerve cell adhesion, migration, and development of the central nervous system. However, their role in the regulation of several aspects of tumor progression has eventually emerged. There are over 30 genes encoding the semaphorins, which are divided into eight subclasses. It has been reported that some members of semaphorin classes are antiangiogenic and antimetastatic in nature, whereas others act as proangiogenic and prometastatic genes. Because of their differential expression and role in angiogenesis and metastasis, semaphorins emerged as one of the important prognostic factors for appraising breast cancer progression.

Neuroimmune semaphorins as costimulatory molecules and beyond

Several neuronal guidance proteins, known as semaphorin molecules, function in the immune system. This dual tissue performance has led to them being defined as "neuroimmune semaphorins". They have been shown to regulate T cell activation by serving as costimulatory molecules. Similar to classical costimulatory molecules, neuroimmune semaphorins are either constitutively or inducibly expressed on immune cells. In contrast to the classical costimulatory molecule function, the action of neuroimmune semaphorins requires the presence of two signals, the first one provided by TCR/MHC engagement, and the second one provided by B7/CD28 interaction. Thus, neuroimmune semaphorins serve as a "signal three" for immune cell activation and regulate the overall intensity of immune response. The current knowledge on their structures, multiple receptors, specific cell/tissue/organ expression, and distinct functions in different diseases are summarized and discussed in this review.

Silencing of semaphorin 3C suppresses cell proliferation and migration in MCF-7 breast cancer cells

Previous studies have suggested that semaphorin 3C (SEMA3C) is involved in the tumorigenesis and metastasis of a number of types of cancer. The aim of the present study was to investigate the role of SEMA3C in the proliferation and migration of MCF-7 breast cancer cells. Small interfering (si)RNA sequences targeting SEMA3C were constructed and transfected into MCF-7 cells in order to silence the expression of SEMA3C. Cell proliferation and migration were measured using CCK-8 and Transwell assays, respectively. Transfection with SEMA3C siRNA significantly downregulated the expression of SEMA3C in MCF-7 cells, and significantly suppressed cell proliferation and migration. Therefore, SEMA3C-targeted siRNA may be of potential use for the early diagnosis and treatment of breast cancer.

Current drug design to target the Semaphorin/Neuropilin/Plexin complexes

The Semaphorin/Neuropilin/Plexin (SNP) complexes control a wide range of biological processes. Consistently, activity deregulation of these complexes is associated with many diseases. The increasing knowledge on SNP had in turn validated these molecular complexes as novel therapeutic targets. Targeting SNP activities by small molecules, antibodies and peptides or by soluble semaphorins have been proposed as new therapeutic approach. This review is focusing on the latest demonstration of this potential and discusses some of the key questions that need to be addressed before translating SNP targeting into clinically relevant approaches.

Chemorepellent Semaphorin 3E Negatively Regulates Neutrophil Migration In Vitro and In Vivo

Neutrophil migration is an essential step in leukocyte trafficking during inflammatory responses. Semaphorins, originally discovered as axon guidance cues in neural development, have been shown to regulate cell migration beyond the nervous system. However, the potential contribution of semaphorins in the regulation of neutrophil migration is not well understood. This study examines the possible role of a secreted chemorepellent, Semaphorin 3E (Sema3E), in neutrophil migration. In this study, we demonstrated that human neutrophils constitutively express Sema3E high-affinity receptor, PlexinD1. Sema3E displayed a potent ability to inhibit CXCL8/IL-8-induced neutrophil migration as determined using a microfluidic device coupled to real-time microscopy and a transwell system in vitro. The antimigratory effect of Sema3E on human neutrophil migration was associated with suppression of CXCL8/IL-8-mediated Ras-related C3 botulinum toxin substrate 1 GTPase activity and actin polymerization. We further addressed the regulatory role of Sema3E in the regulation of neutrophil migration in vivo. Allergen airway exposure induced higher neutrophil recruitment into the lungs of Sema3e^-/- mice compared with wild-type controls. Administration of exogenous recombinant Sema3E markedly reduced allergen-induced neutrophil recruitment into the lungs, which was associated with alleviation of allergic airway inflammation and improvement of lung function. Our data suggest that Sema3E could be considered an essential regulatory mediator involved in modulation of neutrophil migration throughout the course of neutrophilic inflammation.