Gene expression disorders of innate antibacterial signaling pathway in pancreatic cancer patients: implications for leukocyte dysfunction and tumor progression

Tumor Necrosis Factor Receptor-Associated Factor 6 and Human Cancer: A Systematic Review of Mechanistic Insights, Functional Roles, and Therapeutic Potential

Cancer imposes a substantial burden and its incidence is persistently increasing in recent years. Cancer treatment has been difficult due to its inherently complex nature. The tumor microenvironment (TME) includes a complex interplay of cellular and noncellular constituents surrounding neoplastic cells, intricately contributing to the tumor initiation and progression. This critical aspect of tumors involves a complex interplay among cancer, stromal, and inflammatory cells, forming an inflammatory TME that promotes tumorigenesis across all stages. Tumor necrosis factor receptor-associated factor 6 (TRAF6) is implicated in modulating various critical processes linked to tumor pathogenesis, including but not limited to the regulation of tumor cell proliferation, invasion, migration, and survival. Furthermore, TRAF6 prominently contributes to various immune and inflammatory pathways. The TRAF6-mediated activation of nuclear factor (NF)-κB in immune cells governs the production of proinflammatory cytokines. These cytokines sustain inflammation and stimulate tumor growth by activating NF-κB in tumor cells. In this review, we discuss various types of tumors, including gastrointestinal cancers, urogenital cancers, breast cancer, lung cancer, head and neck squamous cell carcinoma, uterine fibroids, and glioma. Employing a rigorous and systematic approach, we comprehensively evaluate the functional repertoire and potential roles of TRAF6 in various cancer types, thus highlighting TRAF6 as a compelling and emerging therapeutic target worthy of further investigation and development.

Association between disease-related malnutrition and innate immunity gene expression in critically ill patients at intensive care unit admission

The aim of the study was to analyse the relationship between nutritional disorders and the expression of innate antibacterial response genes in patients admitted to the intensive care unit (ICU). In 46 patients with severe malnutrition and life-threatening surgical complications, nutritional status tests were performed on the basis of the NRS 2002 (Nutritional Risk Screening) scale, cytokine, albumin, C-reactive protein concentrations, anthropometric tests, and body composition analysis. Concurrently, the expression of Toll-like receptor 2, NOD1, TRAF6, and HMGB1 genes was determined in peripheral blood leukocytes at the mRNA level using real-time polymerase chain reaction. It was found that both the nutritional status and the gene expression changed depending on the group of patients studied (including the group of survivors vs. non-survivors). Significant correlations were found between the results of routine tests used in the diagnostics of malnutrition (including NRS 2002, resistance, reactance, phase angle, excess of extracellular water) and the expression of the studied genes. Moreover, the expression of TRAF6 and HMGB1 genes correlated with the Acute Physiology and Chronic Health Evaluation II scale and the age of the patients. The results of the research suggest that the expression of innate antibacterial response genes may be a new diagnostic tool complementing the assessment of nutritional disorders in surgical patients admitted to the ICU. These tests may be helpful in providing more accurate diagnostics of the genetic effects of malnutrition and in the monitoring of patients for whom nutritional treatment is planned to support the functions of the immune system, thereby increasing the effectiveness of this type of treatment in the ICU.

Proteome profiling of triple negative breast cancer cells overexpressing NOD1 and NOD2 receptors unveils molecular signatures of malignant cell proliferation

Background

Triple negative breast cancer (TNBC) is a malignancy with very poor prognosis, due to its aggressive clinical characteristics and lack of response to receptor-targeted drug therapy. In TNBC, immune-related pathways are typically upregulated and may be associated with a better prognosis of the disease, encouraging the pursuit for immunotherapeutic options. A number of immune-related molecules have already been associated to the onset and progression of breast cancer, including NOD1 and NOD2, innate immune receptors of bacterial-derived components which activate pro-inflammatory and survival pathways. In the context of TNBC, overexpression of either NOD1or NOD2 is shown to reduce cell proliferation and increase clonogenic potential in vitro. To further investigate the pathways linking NOD1 and NOD2 signaling to tumorigenesis in TNBC, we undertook a global proteome profiling of TNBC-derived cells ectopically expressing each one of these NOD receptors.

Results

We have identified a total of 95 and 58 differentially regulated proteins in NOD1- and NOD2-overexpressing cells, respectively. We used bioinformatics analyses to identify enriched molecular signatures aiming to integrate the differentially regulated proteins into functional networks. These analyses suggest that overexpression of both NOD1 and NOD2 may disrupt immune-related pathways, particularly NF-κB and MAPK signaling cascades. Moreover, overexpression of either of these receptors may affect several stress response and protein degradation systems, such as autophagy and the ubiquitin-proteasome complex. Interestingly, the levels of several proteins associated to cellular adhesion and migration were also affected in these NOD-overexpressing cells.

Conclusions

Our proteomic analyses shed new light on the molecular pathways that may be modulating tumorigenesis via NOD1 and NOD2 signaling in TNBC. Up- and downregulation of several proteins associated to inflammation and stress response pathways may promote activation of protein degradation systems, as well as modulate cell-cycle and cellular adhesion proteins. Altogether, these signals seem to be modulating cellular proliferation and migration via NF-κB, PI3K/Akt/mTOR and MAPK signaling pathways. Further investigation of altered proteins in these pathways may provide more insights on relevant targets, possibly enabling the immunomodulation of tumorigenesis in the aggressive TNBC phenotype.

Electronic supplementary material

The online version of this article (10.1186/s12864-019-5523-6) contains supplementary material, which is available to authorized users.

Harnessing the untapped potential of nucleotide-binding oligomerization domain ligands for cancer immunotherapy

In the last decade, cancer immunotherapy has emerged as an effective alternative to traditional therapies such as chemotherapy and radiation. In contrast to the latter, cancer immunotherapy has the potential to distinguish between cancer and healthy cells, and thus to avoid severe and intolerable side‐effects, since the cancer cells are effectively eliminated by stimulated immune cells. The cytosolic nucleotide‐binding oligomerization domains 1 and 2 receptors (NOD1 and NOD2) are important components of the innate immune system and constitute interesting targets in terms of strengthening the immune response against cancer cells. Many NOD ligands have been synthesized, in particular NOD2 agonists that exhibit favorable immunostimulatory and anticancer activity. Among them, mifamurtide has already been approved in Europe by the European Medicine Agency for treating patients with osteosarcoma in combination with chemotherapy after complete surgical removal of the primary tumor. This review is focused on NOD receptors as promising targets in cancer immunotherapy as well as summarizing current knowledge of the various NOD ligands exhibiting antitumor and even antimetastatic activity in vitro and in vivo.

The role of cancer-associated fibroblast MRC-5 in pancreatic cancer

Background: Our previous study showed that cancer-associated fibroblast MRC-5 promoted hepatocellular carcinoma progression by enhancing migration and invasion capability. However, few studies have explored the role of MRC-5 in pancreatic cancer (PC). In this study, we examined the exact role and associated mechanisms of MRC-5. Methods: The conditioned media for MRC-5 was used to culture PC cell lines SW1990 and PANC-1. Cell proliferation was compared based on colony formation assays of PC cells in normal media and of PC cells cultured with conditioned media of MRC-5. Cell migration and invasion were assayed by transwell chambers. The expression of EMT-related proteins and apoptosis-related proteins was evaluated using Western blot. And confocal microscopy was used to further detect the expression of EMT-related proteins. qRT-PCR was used to confirm the expression changes of related genes at the mRNA level. We also used flow cytometry to examine the cell cycle, apoptotic rate, and expression of CD3, CD4, CD14, CD25, CD45, CD61, CD90, TLR1, and TLR4. Results: MRC-5 repressed the colony formation ability of PC cells and significantly inhibited cell migration and invasion potential. MRC-5 induced S-phase cell cycle arrest but did not augment the apoptotic effects in PC cells. We hypothesized that the weakened malignant biological behavior of PC cells was correlated with MRC-5-induced altered expression of the cancer stem cell marker CD90; the immune-related cell surface molecules CD14, CD25, TLR4, and TLR1; and cell polarity complexes Par, Scribble, and Crumbs. Conclusion: MRC-5 limits the malignant activities of PC cells by suppressing cancer stem cell expansion, remolding epithelial polarity, and blocking the protumoral cascade reaction coupled to TLR4, TLR1, CD14, and CD25.

Dysregulation of signaling pathways associated with innate antibacterial immunity in patients with pancreatic cancer

Disorders of innate antibacterial response are of fundamental importance in the development of gastrointestinal cancers, including pancreatic cancer. Multi-regulatory properties of the Toll-like receptors (TLRs) (e.g., regulation of proliferation, the activity of NF-κB, gene transcription of apoptosis proteins, regulation of angiogenesis, HIF-1α protein expression) are used in experimental studies to better understand the pathogenesis of pancreatic cancer, for early diagnosis, and for more effective therapeutic intervention. There are known numerous examples of TLR agonists (e.g., TLR2/5 ligands, TLR6, TLR9) of antitumor effect. The direction of these studies is promising, but a small number of them does not allow for an accurate assessment of the impact of TLR expression disorders, proteins of these signaling pathways, or attempts to block or stimulate them, on the results of treatment of pancreatic cancer patients. It is known, however, that the expression disorders of proteins of innate antibacterial response signaling pathways occur not only in tumor tissue but also in peripheral blood leukocytes of pancreatic cancer patients (e.g., increased expression of TLR4, NOD1, TRAF6), which is one of the most important factors facilitating further tumor development. This review mainly focuses on the genetic aspects of signaling pathway disorders associated with innate antibacterial response in the pathogenesis and diagnosis of pancreatic cancer.

Innate immunity gene expression changes in critically ill patients with sepsis and disease-related malnutrition

The aim of this study was an attempt to determine whether the expression of genes involved in innate antibacterial response (TL R2, NOD 1, TRAF6, HMGB 1 and Hsp70) in peripheral blood leukocytes in critically ill patients, may undergo significant changes depending on the severity of the infection and the degree of malnutrition. The study was performed in a group of 128 patients with infections treated in the intensive care and surgical ward. In 103/80.5% of patients, infections had a severe course (sepsis, severe sepsis, septic shock, mechanical ventilation of the lungs). Clinical monitoring included diagnosis of severe infection (according to the criteria of the ACC P/SCC M), assessment of severity of the patient condition and risk of death (APACHE II and SAPS II), nutritional assessment (NRS 2002 and SGA scales) and the observation of the early results of treatment. Gene expression at the mRNA level was analyzed by real-time PCR. The results of the present study indicate that in critically ill patients treated in the IC U there are significant disturbances in the expression of genes associated with innate antimicrobial immunity, which may have a significant impact on the clinical outcome. The expression of these genes varies depending on the severity of the patient condition, severity of infection and nutritional status. Expression disorders of genes belonging to innate antimicrobial immunity should be diagnosed as early as possible, monitored during the treatment and taken into account during early therapeutic treatment (including early nutrition to support the functions of immune cells).