239 research outputs found
Genetic polymorphisms of CYP1A1, GSTM1 and GSTT1 genes and lung cancer risk
Genetic polymorphisms of the genes encoding for the xenobiotic metabolizing enzymes result in individual variations in the efficiency of detoxification of environmental carcinogens, and have been extensively associated with variable risk for lung neoplasms in different ethnic and environmental backgrounds. In this study, using PCR-RFLP based assays, we investigated the distribution of genetic polymorphisms in CYP1A1, GSTM1 and GSTT1 genes in Greek lung cancer patients (N=122) and healthy controls (N=178). The frequency of CYP1A1 m1 homozygous genotype was 0.04 in patients and 0.02 in controls (detected in 4.10% of patients and in 1.69% of controls, respectively), that of GSTM1 null genotype was 0.52 in patients and 0.54 in controls, whereas those of GSTT1 null genotype was 0.17 and 0.11, in patients and controls, respectively. The GSTM1 null genotype was more frequent in adenocarcinoma, as well as in lung cancer patients with history of chronic obstructive pulmonary disease (COPD). The GSTT1 null genotype correlated with advanced age of the patients at the time of diagnosis. Three combinations of rare genotypes - in subjects carrying simultaneously deviations from the common genotype in more than one gene - were over-represented in lung cancer patients, compared to control population, and were furthermore significantly associated with history of heavy tobacco consumption in lung cancer patients. The results imply involvement of specific genotype combinations of CYP1A1, GSTM1 and GSTT1 alleles in the development of lung cancer in heavy smokers
Cytochrome P450 CYP1A1: wider roles in cancer progression and prevention
CYP1A1 is one of the main cytochrome P450 enzymes, examined extensively for its capacity to activate compounds with carcinogenic properties. Continuous exposure to inhalation chemicals and environmental carcinogens is thought to increase the level of CYP1A1 expression in extrahepatic tissues, through the aryl hydrocarbon receptor (AhR). Although the latter has long been recognized as a ligand-induced transcription factor, which is responsible for the xenobiotic activating pathway of several phase I and phase II metabolizing enzymes, recent evidence suggests that the AhR is involved in various cell signaling pathways critical to cell cycle regulation and normal homeostasis. Disregulation of these pathways is implicated in tumor progression. In addition, it is becoming increasingly evident that CYP1A1 plays an important role in the detoxication of environmental carcinogens, as well as in the metabolic activation of dietary compounds with cancer preventative activity. Ultimately the contribution of CYP1A1 to cancer progression or prevention may depend on the balance of procarcinogen activation/detoxication and dietary natural product extrahepatic metabolism
Leveraging New Plans in AgentSpeak(PL)
Many papers have been written on the anticancer properties of dietary flavonoids, and a range of potential mechanisms of action of flavonoids. However, most dietary flavonoids - notably polyphenolic flavonoidsâhave very poor ADME properties, and the levels necessary to stop growth of tumour cells cannot be sustained in a human body trough dietary intake alone. At present no flavonoid based drugs are clinically used in cancer therapy. Thus, whereas epidemiological and pre-clinical data seem to indicate a high potential for flavonoids, from the point of view of the pharmaceutical industry and drug developers, they are considered poor candidates. The flavonesâwhich constitute a subgroup of the flavonoidsâshow some structural analogy with oestrogen and are known to interact with human oestrogen receptors, either as agonist or as antagonist. They are classed as phytoestrogens, and may play a role in cancer prevention through a mechanism of action possibly similar to that of the clinically used medication tamoxifen. Flavones are abundantly present in common fruits and vegetables, many of which have been associated with cancer prevention. Their phytoestrogen activity makes that they can assert their biological action at concentrations that are realistically achievable in the human systemic circulation
Cutaneous melanoma: From pathogenesis to therapy (Review)
In less than 10 years, melanoma treatment has been
revolutionized with the approval of tyrosine kinase inhibitors
and immune checkpoint inhibitors, which have been shown
to have a significant impact on the prognosis of patients with
melanoma. The early steps of this transformation have taken
place in research laboratories. The mitogen-activated protein
kinase (MAPK) pathway, phosphoinositol-3-kinase (PI3K)
pathway promote the development of melanoma through
numerous genomic alterations on different components of these
pathways. Moreover, melanoma cells deeply interact with the
tumor microenvironment and the immune system. This knowledge has led to the identification of novel therapeutic targets and
treatment strategies. In this review, the epidemiological features
of cutaneous melanoma along with the biological mechanisms
involved in its development and progression are summarized.
The current state-of-the-art of advanced stage melanoma treatment strategies and the currently available evidence of the use of
predictive and prognostic biomarkers are also discussed
Peripheral monocytes from diabetic patients with coronary artery disease display increased bFGF and VEGF mRNA expression
BACKGROUND: Macrophages can produce vascular endothelial growth factor (VEGF) in response to hypoxia, transforming growth factor ÎČ1 (TGF-ÎČ1), angiotensin II, basic fibroblast growth factor (bFGF), and interleukin-1. These factors have been found in the serum of coronary artery disease (CAD) patients as well as in atherosclerotic lesions. The aim of the present study was to test the hypothesis that the expression of VEGF, TGF-ÎČ1 and bFGF in peripheral monocytes and lymphocytes is related to CAD. METHODS: Human Mononuclear cells and lymphocytes from peripheral blood were isolated from 53 donors undergoing angiography. Seventeen were found to be healthy and 36 were diagnosed with CAD. The respective mRNAs were extracted and quantified. RESULTS: The statistical analysis revealed a significant increase of the basal level expression for macrophage VEGF and bFGF in the CAD SA (stable angina) patient group compared to the noCAD (control) (p = 0.041 and p = 0.022 respectively) and CAD UA (unstable angina) (p = 0.024 and p = 0.005 respectively) groups, which was highly dependent on the diabetic status of the population. Furthermore, we demonstrated with an in vitro cell culture model that the levels of VEGF and bFGF in monocytes of healthy donors are not affected by short term exposure to increased glucose levels (usually observed in the diabetic patients) and/or statin. CONCLUSION: Our findings display a statistically significant association of the increased VEGF and bFGF levels in peripheral monocytes, with stable angina and diabetes in coronary artery disease. The results give new insight to CAD and the impaired collateral vessel formation in diabetics
Miliary tuberculosis with no pulmonary involvement in myelodysplastic syndromes: a curable, yet rarely diagnosed, disease: case report and review of the literature
<p>Abstract</p> <p>Background</p> <p>Although tuberculosis is not uncommon among patients with myelodysplastic syndrome (MDS), only a few reports of such patients suffering from miliary tuberculosis (MT) exist. MT often presents as a fever of unknown origin and it is a curable disease, yet fatal if left untreated.</p> <p>Case presentation</p> <p>We report a case of MT with no clinical or laboratory indications of pulmonary involvement in a patient with MDS, and review the relevant literature. <it>Mycobacterium tuberculosis </it>was isolated from the liquid culture of a bone marrow aspirate.</p> <p>Conclusion</p> <p>Even if the initial diagnostic investigation for a fever of obscure etiology is negative, MT should not be excluded from the differential diagnosis list. Since it is a curable disease, persistent and vigorous diagnostic efforts are warranted. In suspected cases, mycobacterial blood cultures should be collected as soon as possible after hospital admission and early bone marrow aspirate with mycobacterial cultures is advocated.</p
Detection of herpes simplex virus Type-1 in patients with fibrotic lung diseases
The current study intends to investigate i) the incidence of herpes viruses including Herpes Simplex Virus type-1 (HSV-1), Cytomegalovirus (CMV) and Human Herpes Virus -6, -7, -8 (HHV6, HHV7, HHV8) in two biological samples, bronchoalveolar lavage fluid (BALF) and lung tissue biopsy, in different forms of pulmonary fibrosis, and ii) the induction of molecular pathways involved in fibrosis by herpesvirus infection in primary cell cultures. PCR was employed for the detection of CMV, HHV6-8 and HSV-1 DNA in lung specimens (4 controls and 11 IPF specimens) and BALF pellet [6 controls and 20 fibrotic Idiopathic Intestitial Pneumonias (f-IIPs) samples: 13 idiopathic pulmonary fibrosis (IPF) and 7 nonspecific idiopathic interstitial pneumonia (NSIP)] samples. Among all herpesviruses tested, HSV-1 was detected in 1/11 (9%) specimens from IPF lung tissue and in 2/20 (10%) samples of f-IIPs BALF whereas the control group was negative. Primary cell cultures from BALF of patients with IPF and healthy controls were infected in vitro with wild-type HSV-1 virus and Real Time PCR was employed for the detection of gene transcription of specific axes implicated in lung fibrosis. Primary cell cultures were permissive to HSV-1, resulting in an upregulation of the fibrotic growth factors TGFÎČ1 and FGF, the angiogenetic markers SDF1a, SDF1b, VEGF, FGF and the regulators of tissue wound healing MMP9 and CCR7. Downregulation was noted for the CXCR4 and MMP2 genes, while a different response has been detected in healthy donors regarding the expression of the aforementioned markers. These results implicate for the first time the HSV-1 with Fibrotic Idiopathic Interstitial Pneumonias since the virus presented similar incidence in two different biological samples
Potential interaction of cadmium chloride with pancreatic mitochondria: Implications for pancreatic cancer
Pancreatic cancer (PC) is insidious with a high mortality rate due to the lack of symptomology prior to diagnosis. Mitochondrial involvement in PC development is becoming accepted, and exposure to cadmium (Cd) is suspected of being a risk factor for the development of PC; however, the mechanisms involved remain unclear. In this study, we examined the role of Cd as a mitochondrial toxicant and whether alterations in mitochondrial function may be an underlying cause for the development of PC. In this study, cadmium chloride (CdCl2)-mediated toxicity in hTERT-HPNE and AsPC-1 pancreatic cell lines was determined by MTT assay. We also investigated the release of LDH and the generation of free radicals. Mitochondrial toxicity assays were performed in media containing glucose (25 mM) or galactose (10 mM) and following exposure to CdCl2 (0-100 M) followed by MTT assay. For the confirmation of mitochondrial toxicity, we measured the release of ATP following exposure to CdCl2. Initial experiments confirmed that exposure to CdCl2 did not reduce the viability of either cell line until a concentration of >10 M was used. Non-linear analysis of the response curves revealed lethal concentration 50% (LC50) values for CdCl2 in the HPNE cells of 77 M compared to 42 M in the AsPC-1 cells (P lt 0.01). The CdCl2-mediated mitochondrial toxic effects were greater in the HPNE cells, suggesting a heightened sensitivity to the effects of CdCl2, not due to elevated oxidative stress. Increased mitochondrial toxic sensitivity was indicated by a 73.4% reduction in IC50 values in the HPNE cells cultured in galactose compared to culture in glucose media, whereas the AsPC-1 cells exhibited a 58.8% reduction in IC50 values. In addition, the higher concentration of CdCl2 elicited a significant cell-dependent effect on ATP release in both cell lines, suggestive of CdCl2 being a mitochondrial toxicant. Cell survival was unaffected following exposure to low concentrations of CdCl2; however, exposure did alter mitochondrial function (control cells > tumor cells). Therefore, the findings of this study indicate that the mitochondria may be a site of action for cadmium in promoting tumor development
Self-eating: Friend or foe? The emerging role of autophagy in idiopathic pulmonary fibrosis
Idiopathic pulmonary fibrosis is the most common and severe form of idiopathic interstitial pneumonias. Despite an exponential increase in our understanding of potentially important mediators and mechanisms, the pathogenesis remains elusive, and little therapeutic progress has been made in the last few years. Mortality in 3-5 years is still 50%. Autophagy, a highly conserved homeostatic mechanism necessary for cell survival, has been recently implicated in the pathogenesis of pulmonary disorders. In this paper we aim to highlight some key issues regarding the process of autophagy and its possible association with the pathogenesis of idiopathic pulmonary fibrosis
Neuropilinâ1 as a new potential SARSâCoVâ2 infection mediator implicated in the neurologic features and central nervous system involvement of COVIDâ19
Infection by the severe acute respiratory syndrome (SARS) coronavirus-2 (SARS-CoV-2) is the cause of the new viral infectious disease (coronavirus disease 2019; COVID-19). Emerging evidence indicates that COVID-19 may be associated with a wide spectrum of neurological symptoms and complications with central nervous system (CNS) involvement. It is now well-established that entry of SARS-CoV-2 into host cells is facilitated by its spike proteins mainly through binding to the angiotensin-converting enzyme 2 (ACE-2). Preclinical studies have suggested that neuropilin-1 (NRP1), which is a transmembrane receptor that lacks a cytosolic protein kinase domain and exhibits high expression in the respiratory and olfactory epithelium, may also be implicated in COVID-19 by enhancing the entry of SARS-CoV-2 into the brain through the olfactory epithelium. In the present study, we expand on these findings and demonstrate that the NRP1 is also expressed in the CNS, including olfactory-related regions such as the olfactory tubercles and paraolfactory gyri. This furthers supports the potential role of NRP1 as an additional SARS-CoV-2 infection mediator implicated in the neurologic manifestations of COVID-19. Accordingly, the neurotropism of SARS-CoV-2 via NRP1-expressing cells in the CNS merits further investigation
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