Altered Treg Infiltration after Discoidin Domain Receptor 1 (DDR1) Inhibition and Knockout Promotes Tumor Growth in Lung Adenocarcinoma

Lung cancer is the leading cause of cancer-related death worldwide. Discoidin domain receptor 1 (DDR1), a tyrosine kinase receptor, has been associated with poor prognosis in patients with non-small cell lung cancer (NSCLC). However, its role in tumorigenesis remains poorly understood. This work aimed to explore the impact of DDR1 expression on immune cell infiltration in lung adenocarcinoma. Pharmacological inhibition and knockout of DDR1 were used in an immunocompetent mouse model of KRAS/p53-driven lung adenocarcinoma (LUAD). Tumor cells were engrafted subcutaneously, after which tumors were harvested for investigation of immune cell composition via flow cytometry. The Cancer Genome Atlas (TCGA) cohort was used to perform gene expression analysis of 509 patients with LUAD. Pharmacological inhibition and knockout of DDR1 increased the tumor burden, with DDR1 knockout tumors showing a decrease in CD8+ cytotoxic T cells and an increase in CD4+ helper T cells and regulatory T cells. TCGA analysis revealed that low-DDR1-expressing tumors showed higher FoxP3 (regulatory T-cell marker) expression than high-DDR1-expressing tumors. Our study showed that under certain conditions, the inhibition of DDR1, a potential therapeutic target in cancer treatment, might have negative effects, such as inducing a pro-tumorigenic tumor microenvironment. As such, further investigations are necessary.

Resistance to hormone therapy in breast cancer cells promotes autophagy and EGFR signaling pathway

Breast cancer is the leading cause of cancer deaths for women worldwide. Endocrine therapies represent the cornerstone for hormone-dependent breast cancer treatment. However, in many cases, endocrine resistance is induced with poor prognosis for patients. In the current study, we have developed MCF-7 cell lines resistant to fulvestrant (MCF-7Fulv) and tamoxifen (MCF-7Tam) aiming at investigating mechanisms underlying resistance. Both resistant cell lines exerted lower proliferation capacity in two-dimensional (2-D) cultures but retain estrogen receptor α (ERα) expression and proliferate independent of the presence of estrogens. The established cell lines tend to be more aggressive exhibiting advanced capacity to form colonies, increased expression of epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), and heterodimerization of ERBB family receptors and activation of EGFR downstream pathways like MEK/ERK1/2 and PI3K/AKT. Tyrosine kinase inhibitors tested against resistant MCF-7Fulv and MCF-7Tam cells showed moderate efficacy to inhibit cell proliferation, except for lapatinib, which concomitantly inhibits both EGFR and HER2 receptors and strongly reduced cell proliferation. Furthermore, increased autophagy was observed in resistant MCF-7Fulv and MCF-7Tam cells as shown by the presence of autophagosomes and increased Beclin-1 levels. The increased autophagy in resistant cells is not associated with increased apoptosis, suggesting a cytoprotective role for autophagy that may favor cells' survival and aggressiveness. Thus, by exploiting those underlying mechanisms, new targets could be established to overcome endocrine resistance.NEW & NOTEWORTHY The development of resistance to hormone therapy caused by both fulvestrant and tamoxifen promotes autophagy with concomitant apoptosis evasion, rendering cells capable of surviving and growing. The fact that resistance also triggers ERBB family signaling pathways, which are poorly inhibited by tyrosine kinase inhibitors might attribute to cells' aggressiveness. It is obvious that the development of endocrine therapy resistance involves a complex interplay between deregulated ERBB signaling and autophagy that may be considered in clinical practice.

Tumor-Mediated Neutrophil Polarization and Therapeutic Implications

Neutrophils are immune cells with reported phenotypic and functional plasticity. Tumor-associated neutrophils display many roles during cancer progression. Several tumor microenvironment (TME)-derived factors orchestrate neutrophil release from the bone marrow, recruitment and functional polarization, while simultaneously neutrophils are active stimulators of the TME by secreting factors that affect immune interactions and subsequently tumor progression. Successful immunotherapies for many cancer types and stages depend on the targeting of tumor-infiltrating lymphocytes. Neutrophils impact the success of immunotherapies, such as immune checkpoint blockade therapies, by displaying lymphocyte suppressive properties. The identification and characterization of distinct neutrophil subpopulations or polarization states with pro- and antitumor phenotypes and the identification of the major TME-derived factors of neutrophil polarization would allow us to harness the full potential of neutrophils as complementary targets in anticancer precision therapies.

Myeloperoxidase: Growing importance in cancer pathogenesis and potential drug target

Myeloperoxidase is a heme-peroxidase which makes up approximately 5% of the total dry cell weight of neutrophils where it is predominantly found in the primary (azurophilic) granules. Other cell types, such as monocytes and certain macrophage subpopulations also contain myeloperoxidase, but to a much lesser extent. Initially, the function of myeloperoxidase had been mainly associated with its ability as a catalyzer of reactive oxidants that help to clear pathogens. However, over the past years non-canonical functions of myeloperoxidase have been described both in health and disease. Attention has been specially focused on inflammatory diseases, in which an exacerbate infiltration of leukocytes can favor a poorly-controlled production and release of myeloperoxidase and its oxidants. There is compelling evidence that myeloperoxidase derived oxidants contribute to tissue damage and the development and propagation of acute and chronic vascular inflammation. Recently, neutrophils have attracted much attention within the large diversity of innate immune cells that are part of the tumor microenvironment. In particular, neutrophil-derived myeloperoxidase may play an important role in cancer development and progression. This review article aims to provide a comprehensive overview of the roles of myeloperoxidase in the development and progression of cancer. We propose future research approaches and explore prospects of inhibiting myeloperoxidase as a strategy to fight against cancer.

Monoacylglycerol lipase deficiency in the tumor microenvironment slows tumor growth in non-small cell lung cancer

Monoacylglycerol lipase (MGL) expressed in cancer cells influences cancer pathogenesis but the role of MGL in the tumor microenvironment (TME) is less known. Using a syngeneic tumor model with KP cells (KrasLSL-G12D/p53fl/fl; from mouse lung adenocarcinoma), we investigated whether TME-expressed MGL plays a role in tumor growth of non-small cell lung cancer (NSCLC). In sections of human and experimental NSCLC, MGL was found in tumor cells and various cells of the TME including macrophages and stromal cells. Mice treated with the MGL inhibitor JZL184 as well as MGL knock-out (KO) mice exhibited a lower tumor burden than the controls. The reduction in tumor growth was accompanied by an increased number of CD8+ T cells and eosinophils. Naïve CD8+ T cells showed a shift toward more effector cells in MGL KOs and an increased expression of granzyme-B and interferon-γ, indicative of enhanced tumoricidal activity. 2-arachidonoyl glycerol (2-AG) was increased in tumors of MGL KO mice, and dose-dependently induced differentiation and migration of CD8+ T cells as well as migration and activation of eosinophils in vitro. Our results suggest that next to cancer cell-derived MGL, TME cells expressing MGL are responsible for maintaining a pro-tumorigenic environment in tumors of NSCLC.

Identification of Novel Low-Density Neutrophil Markers Through Unbiased High-Dimensional Flow Cytometry Screening in Non-Small Cell Lung Cancer Patients

Neutrophils have been described as a phenotypically heterogeneous cell type that possess both pro- and anti-tumor properties. Recently, a subset of neutrophils isolated from the peripheral blood mononuclear cell (PBMC) fraction has been described in cancer patients. These low-density neutrophils (LDNs) show a heterogeneous maturation state and have been associated with pro-tumor properties in comparison to mature, high-density neutrophils (HDNs). However, additional studies are necessary to characterize this cell population. Here we show new surface markers that allow us to discriminate between LDNs and HDNs in non-small cell lung cancer (NSCLC) patients and assess their potential as diagnostic/prognostic tool. LDNs were highly enriched in NSCLC patients (median=20.4%, range 0.3-76.1%; n=26) but not in healthy individuals (median=0.3%, range 0.1-3.9%; n=14). Using a high-dimensional human cell surface marker screen, we identified 12 surface markers that were downregulated in LDNs when compared to HDNs, while 41 surface markers were upregulated in the LDN subset. Using flow cytometry, we confirmed overexpression of CD36, CD41, CD61 and CD226 in the LDN fraction. In summary, our data support the notion that LDNs are a unique neutrophil population and provide novel targets to clarify their role in tumor progression and their potential as diagnostic and therapeutic tool.

Abstract 2823: Exploring the role of neutrophil myeloperoxidase in lung cancer

The aim of this study is to investigate whether myeloperoxidase, a neutrophil-derived molecule in the tumor microenvironment, can influence tumor growth in lung cancer. Lung cancer is the leading cause of cancer related deaths worldwide. Chronic inflammation plays a key role in lung cancer and some studies point out the role of neutrophils as critical mediators of lung carcinogenesis. In this context, some of the neutrophil granule components have been proposed to contribute to tumor development. One of these molecules is myeloperoxidase. Myeloperoxidase is a heme peroxidase enzyme that generates reactive oxygen/nitrogen species and is most abundantly expressed in neutrophils. Upon neutrophil activation, during acute inflammation or in the tumor microenvironment, MPO is secreted into the extracellular milieu during degranulation and utilizes H2O2 to hypochlorous acid that reacts with surrounding proteins and cell surface molecules and thereby can alter signaling pathways and cell functions. So far, we have found some evidence on myeloperoxidase acting in favor of tumor development. In vivo, LSL-K-ras/MPO-/- mice revealed prolonged survival and reduced tumor burden when compared to LSL-K-ras/MPO+/+ mice. Consistently, in a heterotopic syngeneic tumor mouse model, MPO knockout mice (C57/B6-J/MPO-/-) displayed smaller tumors in comparison to the WT littermates. In vitro, myeloperoxidase is able to bind, internalize and preserve its enzymatic activity in human lung adenocarcinoma A549 cells. Furthermore, A549 cells showed increased proliferation and reduced apoptosis after MPO treatment as well as an enhanced phosphorylation of Akt and Erk proteins. According to our current results, myeloperoxidase may play a role in the development of lung cancer by regulating cancer cell function. Moreover, this project sheds light on the role of neutrophil-derived molecules as key players in the context of tumor growth.

Citation Format: Paulina Valadez-Cosmes, Nejra Cosic, Melanie Kienzl, Kathrin Maitz, Sofia Raftopoulou, A. McGarry Houghton, Akos Heinemann, Michael J. Davies, Julia Kargl. Exploring the role of neutrophil myeloperoxidase in lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2823.

Biofunctional Feed Supplemented With By-products of Olive Oil Production Improves Tissue Antioxidant Profile of Lambs

BACKGROUND/AIM

Olive mill wastewater (OMW) is a byproduct of olive oil production. The aim of the study was to estimate the redox profile of lambs' vital organs after consumption of an OMW-supplemented feed.

MATERIALS AND METHODS

Twenty-four lambs received breast milk until day 15. Then, they were divided in two groups: control and OMW, n=12 each. The control group received standard ration, while the OMW group received OMW enriched feed along with mother's milk until day 42 and animals (n=6 per group) were sacrificed. The remaining 12 received the feeds until day 70 and sacrificed. Tissue samples were collected at day 42 and 70 and specific redox biomarkers were assessed.

RESULTS

Overall, the OMW feed improved tissue redox profile by affecting the glutathione S-transferase (GST) activity and γ-glutamate-cysteine ligase (γ-GCL) expression in all tested tissues. Superoxide dismutase (SOD) activity was not affected.

CONCLUSION

The polyphenol-rich byproduct reinforced lamb redox profile and may putatively improve their wellness and productivity.

Association of IL-10 gene promoter polymorphisms with food allergy susceptibility and serum IL-10 level in a pediatric Caucasian population

BACKGROUND

Interleukin 10 has been shown to play a critical role in the regulation of the immune responses in allergic diseases.

AIM

To investigate if genetic polymorphisms in the promoter region of the IL-10 gene are associated with food allergy (FA) susceptibility in Caucasian pediatric patients with concomitant allergic diseases and IL-10 levels.

METHODS

The single nucleotide polymorphisms (SNPs) at -1082A > G (rs1800896), -819 T > C (rs1800871), and -592A > C (rs1800872) of 62 pediatric patients with IgE-mediated FA were analyzed and correlated with clinical parameters, serum IgE and IL-10 levels. The results were compared with those of 92 healthy controls without FA, personal and/or family history of atopy.

RESULTS

Analysis and comparison of genotype distributions, allele frequencies, and haplotypes showed that none of the genotypes confers an increased risk of FA. The genotype -1082 AA in FA patients was associated with moderate to severe symptoms of FA, the development of atopic asthma, and higher levels of IL-10. In a linear regression study, we confirmed that the genotype -1082 AA acts as an independent factor for the higher levels of IL-10. A positive association was also observed between -819T/C and -592 A/C SNPs and later onset of FA.

CONCLUSION

Polymorphisms in the promoter region of the IL-10 gene are not associated with FA susceptibility in our cohort. In FA patients, -1082 A/G SNPs seem to influence the production of IL-10, the severity of FA symptoms, and the development of atopic asthma in this population.

Noxa upregulation and 5-gene apoptotic biomarker panel in colorectal cancer

BACKGROUND

NOXA and MCL1 are involved in the intrinsic pathway of apoptosis, where Noxa selectively binds to MCL1 and prevents it from inhibiting apoptosis. Both factors are considered as potential tumour biomarkers, while MCL1 has attracted interest as target in cancer. The purpose of this study was to investigate the expression of NOXA and MCL1 in 160 CRC tumour samples, to investigate their significance, also in combination with IAPs, DR5 expression and KRAS gene mutations in CRC.

MATERIALS AND METHODS

Fresh frozen colorectal tissue was obtained from patients undergoing surgery for CRC. Real-time quantitative PCR was performed for the determination of mRNA expression levels. Protein expression was determined immunohistochemically. Differences in the mRNA expression profile were evaluated with the nonparametric Wilcoxon signed ranks test. Statistical analysis was performed with the use of Mann-Whitney U test and receiver-operating characteristic (ROC) curve.

RESULTS

NOXA was found to be overexpressed in CRC tumours (P < .0001), even from early stage. Moreover, NOXA/MCL1 mRNA expression was significantly elevated in tumour samples compared to normal pairs (P < .0001). ROC curve analysis showed that both NOXA expression and its combination with Mcl1 expression have fair discriminatory value between CRC and normal colorectal tissue. Combinatorial ROC analysis revealed the most significant discriminatory value of NOXA, MCL1 with cIAP1 and cIAP2 (AUC = 0.834, P < .0001) as a 5-gene panel of markers.

CONCLUSION

Noxa, Mcl1, DR5, cIAP1 and cIAP2 mRNA expressions are significantly deregulated in CRC and could provide a panel of markers with significant discriminatory value between CRC and normal colorectal tissue.

Structural Study of the DNA: Clock/Bmal1 Complex Provides Insights for the Role of Cortisol, hGR, and HPA Axis in Stress Management and Sleep Disorders

Herein, we deploy an in silico pipeline of structural bioinformatics, thermodynamics, and molecular dynamics to investigate the role of cortisol in circadian rhythms, biorhythms, stress response, and even sleep disorders. Our study shows that high concentrations of cortisol intercalate in the minor groove of DNA. This phenomenon widens the adjacent major grooves and provides the Clock/Bmal1 complex with more space to dock and interact with DNA. Then, the strong charges of cortisol pull the alpha helices of the Clock/Bmal1 complex and bend it inward, thus establishing stronger interactions and prolonged signaling. Our results indicate that elevated cortisol levels play an important role in stress, inflammation, and sleep disorders as a result of prolonged and stronger dsDNA - Clock/Bmal1 interactions.

Human Emotions on the Onset of Cardiovascular and Small Vessel Related Diseases

BACKGROUND/AIM

The aim of the present study was to examine the relation between understanding of emotions and cardiovascular related diseases, namely coronary heart disease, diabetes mellitus and obesity. The uniqueness of this study lies in the fact that it examined the relationship between the cardiovascular related diseases named above and the understanding of emotions in the context of Emotional Intelligence (EI).

PATIENTS AND METHODS

The study was conducted in 300 participants during a 3 year period. All participants completed a self-report questionnaire, assessing various aspects of EI, such as self-emotion appraisal, other emotion appraisal, emotion regulation and use of emotions. As hypothesized, coronary heart disease is a prognostic factor of regulation of emotions.

RESULTS

The present study is an attempt to examine the relation between emotional understanding and cardiovascular related diseases, namely coronary heart disease, diabetes mellitus and obesity. Establishing which diseases are independent risk factors for the understanding of emotions, could have a significant impact on emotional health, through the treatment of these cardiovascular related diseases. Emotions were studied within the theoretical context of Emotional Intelligence (EI), which affects people's physical and mental health.

CONCLUSION

The results of this study emphasize on the relationship of cardiovascular related diseases and psychological characteristics, such as anxiety and anger, being aspects of EI. Additionally, this work fills a gap in the relevant Greek literature, as a first attempt to examine the correlation of EI with cardiovascular related diseases.

Genomic big data hitting the storage bottleneck

During the last decades, there is a vast data explosion in bioinformatics. Big data centres are trying to face this data crisis, reaching high storage capacity levels. Although several scientific giants examine how to handle the enormous pile of information in their cupboards, the problem remains unsolved. On a daily basis, there is a massive quantity of permanent loss of extensive information due to infrastructure and storage space problems.  The motivation for sequencing has fallen behind. Sometimes, the time that is spent to solve storage space problems is longer than the one dedicated to collect and analyse data. To bring sequencing to the foreground, scientists have to slide over such obstacles and find alternative ways to approach the issue of data volume. Scientific community experiences the data crisis era, where, out of the box solutions may ease the typical research workflow, until technological development meets the needs of Bioinformatics. 

Genomic big data hitting the storage bottleneck

During the last decades, there is a vast data explosion in bioinformatics. Big data centres are trying to face this data crisis, reaching high storage capacity levels. Although several scientific giants examine how to handle the enormous pile of information in their cupboards, the problem remains unsolved. On a daily basis, there is a massive quantity of permanent loss of extensive information due to infrastructure and storage space problems. The motivation for sequencing has fallen behind. Sometimes, the time that is spent to solve storage space problems is longer than the one dedicated to collect and analyse data. To bring sequencing to the foreground, scientists have to slide over such obstacles and find alternative ways to approach the issue of data volume. Scientific community experiences the data crisis era, where, out of the box solutions may ease the typical research workflow, until technological development meets the needs of Bioinformatics.

HCV genetics and genotypes dictate future antiviral strategies

At the end of the 1980s, the hepatitis C virus (HCV) was cloned and formally identified as the cause of the majority of non-A and non-B hepatitis cases. Today, around 170 million people worldwide are infected with HCV, making it five times more common than infection with the human immunodeficiency virus (HIV). Several methods exist which mediate the spread of infection. One of the most common and efficient is sharing or re-using injecting equipment; studies have indicated that 80-90% of individuals in some populations of intravenous drug users test positive in serum HCV assays. Contracting HCV from infected blood transfusions was also a major cause of infection before screening tests were introduced in the early 1990s. Other possible, but less common, methods of infection transmission include mother-to-child during pregnancy, sexual contact and nosocomial acquisition (for example between surgical or dialysis patients). It appears that concurrent HIV-1 infection increases the risk of HCV transmission via the mother-to-child or sexual routes.

Insights into the molecular mechanisms of stress and inflammation in ageing and frailty of the elderly

Frailty is a natural state of physical, cognitive and mental decline that is expected in the elderly. The role of inflammation in the pathogenesis of frailty has been hypothesized, and so far many studies have been performed in order to understand the mechanism of action underlying this association. Recent studies support this hypothesis and show a clear association between inflammation, frailty, and age-related disease. Chronic inflammation is key pathophysiologic process that contributes to the frailty directly and indirectly through other intermediate physiologic systems, such as the musculoskeletal, endocrine, and hematologic systems. The complex multifactorial etiologies of frailty also include obesity and other age-related specific diseases. Herein, we investigate the link between chronic inflammation and frailty of the older people. In particular, we present an up-to-date review of the role of cytokines, interleukins, cardiovascular abnormalities, chronic high blood pressure, hyperlipidemia and diabetes in relation to the severity of frailty in the elderly.