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1.
Crit Rev Toxicol ; 53(10): 658-701, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38050998

ABSTRACT

Tobacco use is a major cause of preventable morbidity and mortality globally. Tobacco products, including smokeless tobacco (ST), generally contain tobacco-specific N-nitrosamines (TSNAs), such as N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-butanone (NNK), which are potent carcinogens that cause mutations in critical genes in human DNA. This review covers the series of biochemical and chemical transformations, related to TSNAs, leading from tobacco cultivation to cancer initiation. A key aim of this review is to provide a greater understanding of TSNAs: their precursors, the microbial and chemical mechanisms that contribute to their formation in ST, their mutagenicity leading to cancer due to ST use, and potential means of lowering TSNA levels in tobacco products. TSNAs are not present in harvested tobacco but can form due to nitrosating agents reacting with tobacco alkaloids present in tobacco during certain types of curing. TSNAs can also form during or following ST production when certain microorganisms perform nitrate metabolism, with dissimilatory nitrate reductases converting nitrate to nitrite that is then released into tobacco and reacts chemically with tobacco alkaloids. When ST usage occurs, TSNAs are absorbed and metabolized to reactive compounds that form DNA adducts leading to mutations in critical target genes, including the RAS oncogenes and the p53 tumor suppressor gene. DNA repair mechanisms remove most adducts induced by carcinogens, thus preventing many but not all mutations. Lastly, because TSNAs and other agents cause cancer, previously documented strategies for lowering their levels in ST products are discussed, including using tobacco with lower nornicotine levels, pasteurization and other means of eliminating microorganisms, omitting fermentation and fire-curing, refrigerating ST products, and including nitrite scavenging chemicals as ST ingredients.


Subject(s)
Neoplasms , Nitrosamines , Tobacco, Smokeless , Humans , Carcinogens/toxicity , Mutagens , Neoplasms/chemically induced , Nitrates , Nitrites , Nitrosamines/toxicity , Nitrosamines/chemistry , Nitrosamines/metabolism , Tobacco, Smokeless/toxicity
2.
Nicotine Tob Res ; 25(7): 1361-1368, 2023 Jun 09.
Article in English | MEDLINE | ID: mdl-36943313

ABSTRACT

BACKGROUND: To reduce the harmful health effects of combustible cigarette smoke (CS), some (CS) users attempt to substitute CS with electronic cigarettes (ECIG) and/or heated tobacco products (HTP). In this animal study, we evaluated the acute effects of substituting CS consumption with ECIG or HTP thus mimicking the dual users' approach, on the lungs of a mouse model. METHODS: C57BL/6 mice were divided into Control, ECIG, HTP, CS, ECIG + CS, HTP + CS, and HTP + ECIG groups. Animals were exposed for 3 hours in AM and PM sessions to either air, CS, ECIG, or HTP for seven days. Lung injury was assessed by: wet to dry (W/D) ratio, albumin concentration in bronchoalveolar lavage fluid, expression of IL-1ß, IL-6, and TNF-α, histopathology examination, reactive oxygen species (ROS) production, and assessment of cellular apoptosis. RESULTS: W/D ratio was significantly increased in mice exposed to CS only. Albumin leak and expression of IL-1ß, IL-6, and TNF-a were elevated in CS, ECIG + CS, and HTP + CS. Histological examination revealed significant inflammatory cells infiltration, as well as collagen deposit in CS, ECIG + CS, HTP + CS. ROS production was significantly increased in CS, ECIG + CS, HTP + CS. Finally, cell death was also significantly increased in CS, ECIG + CS, and HTP + CS. CONCLUSION: In this animal model, substituting 50% of daily CS exposure by either ECIG or HTP exposure did not result in significant attenuation of acute lung injury.


Subject(s)
Acute Lung Injury , Electronic Nicotine Delivery Systems , Tobacco Products , Tobacco Smoke Pollution , Mice , Animals , Reactive Oxygen Species , Interleukin-6 , Mice, Inbred C57BL , Tobacco Products/adverse effects , Disease Models, Animal , Acute Lung Injury/chemically induced , Acute Lung Injury/therapy , Albumins
3.
Haematologica ; 106(5): 1443-1456, 2021 05 01.
Article in English | MEDLINE | ID: mdl-33567810

ABSTRACT

Adult T cell leukemia/lymphoma (ATL) is associated to chronic human T cell leukemia virus type 1 (HTLV-1) infection and carries a poor prognosis. Arsenic trioxide (AS) and interferon-alpha (IFNα) together selectively trigger Tax viral oncoprotein degradation and cure Tax-driven murine ATL. AS/IFNα/zidovudine treatment achieves a high response rate in patients with chronic ATL. Interleukin 10 (IL-10) is an immuno-suppressive cytokine whose expression is activated by Tax. Here we show that, in ATL, AS/IFNα-induced abrogation of leukemia initiating cell activity requires IL-10 expression shutoff. Loss of IL-10 secretion drives production of inflammatory cytokines by the microenvironment, followed by innate immunity-mediated clearance of Taxdriven leukemic cells. Accordingly, anti-IL-10 monoclonal antibodies significantly increased the efficiency of AS/IFNα therapy. These results emphasize the sequential targeting of malignant ATL cells and their immune microenvironment in leukemia initiating cell (LIC) eradication and provide a strong rational to test AS/IFNα/anti-IL10 combination in ATL.


Subject(s)
Human T-lymphotropic virus 1 , Leukemia-Lymphoma, Adult T-Cell , Adult , Animals , Humans , Immunity, Innate , Interferon-alpha , Interleukin-10/genetics , Leukemia-Lymphoma, Adult T-Cell/drug therapy , Mice , Tumor Microenvironment
4.
Cancer ; 125(16): 2818-2828, 2019 08 15.
Article in English | MEDLINE | ID: mdl-31034603

ABSTRACT

BACKGROUND: Tyrosine kinase inhibitors (TKIs) are the standard treatment for chronic myeloid leukemia (CML). Despite their clinical success, TKIs are faced with challenges such as treatment resistance, which may be driven by kinase domain mutations, and frequent disease relapse upon the cessation of treatment. The combination of arsenic trioxide (ATO) and interferon-α (IFN) was previously demonstrated to inhibit proliferation and induce apoptosis in CML cell lines, prolong the survival of primary wild-type CML mice, and dramatically decrease the activity of leukemia-initiating cells (LICs). METHODS: The ATO/IFN combination was tested in vitro on imatinib (IMN)-resistant K562-R and Ar230-R cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling assays were used to evaluate proliferation and apoptosis, respectively. The acridine orange assay was used to assess autophagy, and quantitative reverse transcription-polymerase chain reaction was used to assess the involvement of the hedgehog (Hh) pathway. In vivo, a retroviral transduction/transplantation T315I BCR-ABL CML mouse model was used to assay the effect of the treatment on survival, tumor burden (histopathology and blood counts), and LIC activity (secondary transplantation). RESULTS: In vitro, ATO/IFN synergized to inhibit proliferation and induce apoptosis of IMN-resistant cells with variant modes of resistance. Furthermore, the preclinical effects of ATO/IFN were associated with induction of autophagy along with inhibition of the Hh pathway. Most remarkably, ATO/IFN significantly prolonged the survival of primary T315I-CML mice and displayed a dramatic impairment of disease engraftment in secondary mice, which reflected decreased LIC activity. CONCLUSIONS: Collectively, the ATO/IFN strategy has been demonstrated to have the potential to lead to durable remissions in TKI-resistant CML preclinical models and to overcome various TKI-specific mechanisms of resistance.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Drug Resistance, Neoplasm/drug effects , Leukemia, Experimental/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Protein Kinase Inhibitors/pharmacology , Animals , Apoptosis/drug effects , Arsenic Trioxide/administration & dosage , Autophagy/drug effects , Fusion Proteins, bcr-abl/metabolism , Hedgehog Proteins/metabolism , Humans , Imatinib Mesylate/pharmacology , Interferon-alpha/administration & dosage , Leukemia, Experimental/pathology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism , Mice, Inbred BALB C , Mice, Transgenic
5.
Mol Biol Rep ; 46(2): 2003-2011, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30701458

ABSTRACT

Recurrent genetic abnormalities confer distinct morphologic features and play a role in determining the clinical behavior, prognosis and adequate treatment of acute leukemia. In the MENA region, only one study targets the frequency of genetic modifications in AML, reporting a higher occurrence of acute promyelocytic leukemia in Lebanon. Determining the frequency of translocations and gene mutations in acute myeloid and lymphoid leukemia cases in an adult patients' population in Lebanon and comparing the resultant genetic profile with the published international molecular profile of adult acute leukemia. Laboratory results of adult patients diagnosed with AML or ALL presenting to AUBMC for genetic profiling between years 2006 until June 2016 were reviewed. Genetic profiling of AML cases in our CAP accredited molecular diagnostics laboratory consists of a validated lab developed RT-PCR for the detection of RUNX1/RUNX1T1, CBFB/MYH11, KMT2A/MLLT3, PML-RARA, and BCR-ABL and mutations in the FLT3 receptor, NPM1, c-kit and CEPBA genes. The ALL panel tests for the presence of BCR-ABL1, ETV6/RUNX1; KMT2A/AFF1, and TCF3-PBX1. We reviewed 580 AML and 175 ALL cases. In the AML cohort, the M:F ratio was 1.3:1 with a mean age of 50 years. t(15;17) was present in 7.6%, t(8;21) in 4.2%, inv(16) in 3.7%, t(9;22) in 2.2% and t(9;11) in 1.7% of cases. FLT3 mutation (ITD or TKD) was present in 25.2% of all cases and 30.1% of Cytogenetics-normal (CN) patients. Mutations of the NPM1 gene was present in 31.4% of AML cases and in 43.8% of CN patients. Double positive (NPM1+/FLT3+) cases accounted for 20% of NK patients. CEBPA and c-kit mutations were detected in 7.3% and 2.4% respectively. In the ALL cohort, the mean age was 37 years. B- and T-lymphoblastic leukemia constituted 84.6% and 15.4% of ALL cases and the M:F ratio was 1.2:1 and 2.86:1 respectively. B-ALL patients were positive for t(9;22) in 14.2%, t(4;11) in 5.4%, t(1;19) in 2.7% and t(12;21) in 1.4%. T-ALL patients were negative for translocations found in our ALL panel. A lower mean age was found in our adult leukemic Lebanese population as compared to the Western cases. Other interesting findings were the lower percentage of inv(16), lower incidence of TCF3-PBX1, and the mild increase in Philadelphia positivity in our AML cohort. In our ALL cohort, t(9;22) positivity was less than expected for adult lymphoblastic leukemia. Full molecular profiling by next generation sequencing is required for further classification of cases into prognostic categories. This study will be a baseline reference for future research and epidemiological data useful for transplant centers and oncologists both in Lebanon and the region.


Subject(s)
Leukemia, Myeloid, Acute/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Adult , Aged , Alleles , Cohort Studies , Female , Gene Expression Profiling/methods , Gene Frequency/genetics , Humans , Lebanon/epidemiology , Leukemia, Myeloid, Acute/metabolism , Longitudinal Studies , Male , Middle Aged , Mutation , Nucleophosmin , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Prognosis , Transcriptome/genetics , Translocation, Genetic
6.
Mol Biol Rep ; 46(4): 3671-3676, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31147859

ABSTRACT

Lung adenocarcinoma patients have variable prognosis due to many factors. Detection of epidermal growth factor receptor (EGFR) activating mutations is one of the factors that implies the need for initiating a first-line EGFR tyrosine kinase inhibitor (TKI) treatment. However, T790M resistance mutation emergence during treatment accounts for most EGFR-TKI drug resistance. The traditional sample taken for T790M mutation analysis is tissue biopsy, but its numerous disadvantages have introduced liquid biopsy as a preferred method for testing. We studied the prevalence of T790M mutation among pulmonary adenocarcinoma patients in Lebanese patients based on liquid biopsy testing the circulating tumor DNA (ctDNA). We have reviewed the laboratory charts of 52 patients who developed resistance on treatment and referred to AUBMC for EGFR T790M Liquid Biopsy to analyze the mutational analysis results for EGFR T790M. In total, 82.6% of the tested lung cancer patients were positive for a specific EGFR mutation. Among these patients, a total 26.9% were positive for T790M, which is comparable to the international prevalence of this mutation. However, for those cases who developed resistance with circulating DNA showing an EGFR mutation, 50% were positive for T790M that is also comparable to the international literature. This is the first report from Lebanon to discuss the prevalence of T790M mutation using liquid biopsy among Lebanese population. An important landmark molecular epidemiology study that will be a reference to all oncologists in Lebanon and the region in assessing the potential for targeted therapy options in the country. In addition, the data will be of an asset to the building international literature related to this disease.


Subject(s)
Adenocarcinoma of Lung/genetics , Antineoplastic Agents/therapeutic use , ErbB Receptors/genetics , Lung Neoplasms/genetics , Protein Kinase Inhibitors/therapeutic use , Adenocarcinoma of Lung/drug therapy , Adenocarcinoma of Lung/pathology , Aged , Aged, 80 and over , Circulating Tumor DNA/genetics , Drug Resistance, Neoplasm/genetics , ErbB Receptors/antagonists & inhibitors , Female , Humans , Lebanon , Liquid Biopsy , Lung/pathology , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Male , Middle Aged , Molecular Targeted Therapy , Mutation , Tertiary Care Centers
7.
Tob Control ; 28(Suppl 2): s104-s112, 2019 06.
Article in English | MEDLINE | ID: mdl-30065075

ABSTRACT

INTRODUCTION: This paper investigates to what extent Framework Convention on Tobacco Control (FCTC) parties have successfully implemented regulatory measures against non-cigarette tobacco product (NCTP) use, considers the challenges and peculiarities in applying such regulations and proposes effective means. DATA AND METHODS: This review was based on many sources mainly: International Legal Consortium, International Tobacco Control, Campaign for Tobacco-Free Kids, FCTC, expert group visits and published literature. FINDINGS AND CONCLUSION: The FCTC provided a framework that applies to all forms of tobacco and this encouraged some parties to adopt control measures against NCTP and to incorporate them into their national tobacco control plans. Although a number of countries have adopted measures specifically targeted towards smokeless and waterpipe tobacco, greater global progress is needed. The strongest achievements have been in protection from exposure to tobacco smoke; controlling advertising, promotion and sponsorship; controlling sales to and by minors; education, communication and public awareness; and packaging and labelling of NCTP. Countries which adopted broad definitions of tobacco products have demonstrated encouraging trends in curbing their use. Future work should address the deep-rooted social acceptance of NCTP, the laxity in their control, their exclusion from regulations in some countries and the failure to subject them to increased taxation. Control measures should also specifically target the initiation risk to youth and adolescents and all factors that contribute to that such as banning flavourings and promotions through social media. Stronger global surveillance of NCTP use, tracking of policy implementation and evaluation of policy impact will provide important evidence to assist parties in fully implementing the FCTC to control their use.


Subject(s)
International Cooperation , Smoking Prevention , Social Control, Formal , Tobacco Products , World Health Organization , Humans
8.
Pediatr Blood Cancer ; 65(1)2018 Jan.
Article in English | MEDLINE | ID: mdl-28675683

ABSTRACT

BACKGROUND AND OBJECTIVES: Second pathology review has been reported to improve accuracy in oncologic diagnoses, including pediatric malignancies. We assessed the impact of second review on the diagnosis of pediatric malignancies at a tertiary care referral center in Beirut, Lebanon. METHODS: Pathology reports of patients treated at the Children's Cancer Institute in Lebanon were retrospectively reviewed for the period 2008-2016 and compared with same samples' diagnoses at St. Jude Children's Research Hospital. Diagnostic disagreements were divided into major, minor, and none based on their effect on diagnosis and/or patient management. RESULTS: Second review was requested for 171 cases, accounting for 19% of all cases during that period. Second opinion was mostly requested for brain tumors (62% of all brain tumor cases) and neuroblastoma for NMYC testing (65% of all neuroblastoma), while hematologic malignancies had the fewest referrals (3% of all hematologic cases). Major disagreements in second review occurred in 20 cases (12% of total), and minor disagreements in 21 cases (12% of total). The largest proportion of major disagreements (71%) occurred in pediatric brain tumors, and novel molecular tests contributed to the diagnosis in 55% of these cases. CONCLUSIONS: The availability of a specialized pediatric neuropathologist and a basic panel of relevant molecular testing are essential for appropriate diagnosis of pediatric brain tumors. Centers that do not have the available infrastructure in place can benefit greatly from second review referrals for this challenging subset of tumors.


Subject(s)
Brain Neoplasms/pathology , Hematologic Neoplasms/pathology , Neuroblastoma/pathology , Adolescent , Child , Child, Preschool , Female , Humans , Infant , Lebanon , Male , Retrospective Studies , Tertiary Care Centers
9.
J Assist Reprod Genet ; 35(9): 1691-1701, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29931406

ABSTRACT

BACKGROUND: Human exposure to environmental pollutants is widespread. It was suggested that exposure to non-essential heavy metals may adversely affect semen development in men. PURPOSE: To evaluate associations between non-essential heavy metals in blood and seminal fluid and semen quality parameters in men. METHODS: Male partners of heterosexual couples were included. The following elements were measured in blood and seminal fluid: lead (Pb), cadmium (Cd), arsenic (As), barium (Ba), mercury (Hg), and uranium (U) using ion-coupled plasma-mass spectrometry. SETTING: The fertility clinic at the American University of Beirut Medical Center. MAIN OUTCOME MEASURES: Semen quality parameters (volume, concentration, total count, progressive motility, viability, and normal morphology). RESULTS: We found that participants with low-quality semen had significantly higher Cd and Ba concentrations in the seminal fluid than participants with normal-quality semen. We also observed significant associations between low sperm viability and higher blood Cd and Ba, as well as higher seminal Pb, Cd, Ba, and U. Furthermore, U concentrations in the seminal fluid were associated with increased odds ratios for below-reference progressive sperm motility and normal morphology. CONCLUSIONS: Environmental exposures to Pb, Cd, Ba, and U appear to adversely influence sperm development in men. In non-occupationally exposed men, measurements of heavy metals in the seminal fluid may be more predictive of below-reference sperm quality parameters than in blood.


Subject(s)
Environmental Exposure , Infertility, Male/blood , Metals, Heavy/blood , Semen Analysis , Adult , Environmental Pollutants/blood , Humans , Infertility, Male/epidemiology , Infertility, Male/pathology , Lebanon , Male , Semen/physiology , Sperm Count , Sperm Motility
10.
East Mediterr Health J ; 24(1): 63-71, 2018 Apr 05.
Article in English | MEDLINE | ID: mdl-29658622

ABSTRACT

BACKGROUND: WHO MPOWER aims to help countries prioritize tobacco control measures in line with the WHO Framework Convention on Tobacco Control. OBJECTIVES: This paper assessed the progress and challenges in implementing the 6 priority policies of MPOWER in countries of the WHO Eastern Mediterranean Region since 2011. METHODS: A checklist was developed and scores assigned based on the MPOWER indicators (maximum score 37). MPOWER data for the Region in the 2015 and 2017 tobacco control reports were extracted and scored. Data from similar analyses for 2011 and 2013 were also included. Countries were ranked by scores for each indicator for 2015 and 2017 and for overall scores for 2011 to 2017. RESULTS: The Islamic Republic of Iran, Egypt and Pakistan had the highest scores in 2015 (33, 29 and 27 respectively) and the Islamic Republic of Iran, Pakistan and Yemen had the highest scores in 2017 (34, 31 and 27 respectively). The indicators with the highest and lowest combined score for all countries were for advertising bans and compliance with smoke-free policies: 67 and 18 respectively in 2015, and 73 and 15 respectively in 2017. Most countries (15/22) had higher total scores in 2017 than 2015: Afghanistan, Bahrain and Syrian Arab Republic had the greatest increases. The total score for the Region increased from 416 out of a maximum score of 814 in 2011 to 471 in 2017. CONCLUSIONS: Although notable achievements have been made in the Region, many challenges to policy implementation remain and require urgent action by governments of the countries of the Region.


Subject(s)
Global Health , Smoking Prevention/organization & administration , Tobacco Industry/legislation & jurisprudence , Tobacco Smoke Pollution/legislation & jurisprudence , Africa, Eastern , Africa, Northern , Health Policy , Humans , Marketing/legislation & jurisprudence , Middle East , Smoking Cessation/methods , Smoking Prevention/legislation & jurisprudence , Taxes/legislation & jurisprudence , World Health Organization
11.
Med Teach ; 39(3): 269-277, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28019135

ABSTRACT

BACKGROUND: There is a mismatch between the requirements of the multifaceted role of academic physicians and their education. Medical institutions use faculty development initiatives to support their junior academic physicians, however, these rarely revolve around academic physician competencies. The aim of this study was to identify these academic physician competencies and develop a competency framework customized to an organizational context. METHODS: The authors conducted semi-structured interviews and Critical Incident Technique with 25 academic physicians at a teaching medical center in the Middle East region inquiring about the behaviors of academic physicians in teaching, clinical, research, and administrative roles. RESULTS: Using content analysis, the authors identified 16 competencies: five "Supporting Competencies", common to all four roles of academic physicians, and 11 "Function-Specific Competencies", specific to the role being fulfilled. The developed framework shared similarities with frameworks reported in the literature but also had some distinctions. CONCLUSIONS: The framework developed represents a step towards closing the gap between the skills medical students are taught and the skills required of academic physicians. The model was customized to the context of the current organization and included a future orientation and addressed the literature calling for increasing focus on the administrative skills of academic physicians.


Subject(s)
Clinical Competence , Faculty, Medical , Physicians , Adult , Curriculum , Female , Hospitals, Teaching , Humans , Interviews as Topic , Male , Middle Aged , Middle East , Qualitative Research
12.
Blood ; 124(13): 2072-80, 2014 Sep 25.
Article in English | MEDLINE | ID: mdl-25035162

ABSTRACT

Adult T-cell leukemia/lymphoma (ATL) is an aggressive neoplasm caused by human T-cell leukemia virus type 1 (HTLV-1). The HTLV-1 oncoprotein Tax plays an important role in ATL pathogenesis. ATL carries a poor prognosis due to chemotherapy resistance, stressing the need for alternative therapies. Here, we investigate the preclinical efficacy of the synthetic retinoid ST1926 in ATL and peripheral T-cell lymphomas. Clinically achievable concentrations of ST1926 induced a dramatic inhibition of cell proliferation in malignant T-cell lines and primary ATL cells with minimal effect on resting or activated normal lymphocytes. ST1926 induced apoptosis, DNA damage, and upregulation of p53 proteins in malignant T cells, whereas it caused an early downregulation of Tax proteins in HTLV-1-positive cells. In murine ATL, oral treatment with ST1926 prolonged survival and reduced leukemia cell infiltration, white blood cell counts, and spleen mass. In spleens of ST1926-treated animals, p53 and p21 proteins were upregulated, poly (ADP-ribose) polymerase was cleaved, and Tax transcripts were reduced. These results highlight the promising use of ST1926 as a targeted therapy for ATL.


Subject(s)
Adamantane/analogs & derivatives , Antineoplastic Agents/pharmacology , Cinnamates/pharmacology , Leukemia-Lymphoma, Adult T-Cell/metabolism , Leukemia-Lymphoma, Adult T-Cell/pathology , Adamantane/administration & dosage , Adamantane/pharmacology , Animals , Antineoplastic Agents/administration & dosage , Apoptosis/drug effects , Caspases/metabolism , Cell Cycle Checkpoints/drug effects , Cell Line, Transformed , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Cinnamates/administration & dosage , DNA Damage , Disease Models, Animal , Drug Evaluation, Preclinical , Gene Expression Regulation, Neoplastic/drug effects , Gene Products, tax/genetics , Gene Products, tax/metabolism , Humans , Leukemia-Lymphoma, Adult T-Cell/drug therapy , Leukemia-Lymphoma, Adult T-Cell/genetics , Leukemia-Lymphoma, Adult T-Cell/mortality , Leukemic Infiltration , Mice , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Xenograft Model Antitumor Assays
13.
Nicotine Tob Res ; 18(5): 613-9, 2016 May.
Article in English | MEDLINE | ID: mdl-26272212

ABSTRACT

BACKGROUND: Smoking electronic cigarettes (ECIG) is promoted as a safer alternative to smoking combustible cigarettes. This study investigates the effects of ECIG aerosol and cigarette smoke (CS) in an animal model and in human alveolar cell cultures (A549). METHODS: Mice were divided into Control, ECIG, and CS. Animals were exposed for 6h/d to either lab air, ECIG or CS, for of 3 days. Total particulate matter exposure for the ECIG was set at higher levels compared to CS. Lung injury was determined by: (1) measurement of wet-to-dry ratio; (2) albumin concentration in the bronchoalveolar lavage fluid; (3) transcriptional expression of inflammatory mediators IL-1ß, IL-6, TNF-α; (4) oxidative stress; (5) assessment of cell death; and (6) lung histopathology. Human alveolar cell cultures were treated with various concentrations of ECIG and CS aerosol extracts and the effects on cell proliferation were evaluated. RESULTS: Wet-to-dry ratio was higher in CS when compared to ECIG. Albumin leak in bronchoalveolar lavage fluid was evident in CS but not in ECIG. ECIG exposure was only associated with a significant increase in IL-1ß. In contrast, CS exposure resulted in significant increases in IL-1ß, IL-6, TNF-α expression, and oxidative stress. TUNEL staining demonstrated significant cell death in CS but not in ECIG. At the cellular level, ECIG and CS extracts reduced cell proliferation, however, CS exhibited effects at lower concentrations. CONCLUSION: Despite higher exposure conditions, ECIG exhibited less toxic effects on lungs of experimental animals and on A549 cell cultures when compared to CS.


Subject(s)
Electronic Nicotine Delivery Systems/adverse effects , Lung/drug effects , Nicotine/pharmacology , Pulmonary Alveoli/drug effects , Smoking/adverse effects , Aerosols , Albumins/analysis , Animals , Bronchoalveolar Lavage Fluid/chemistry , Cell Culture Techniques , Cell Death/drug effects , Disease Models, Animal , Humans , Inflammation/pathology , Lung/metabolism , Lung/pathology , Male , Mice, Inbred C57BL , Oxidative Stress , Pulmonary Alveoli/metabolism , Smoking/metabolism , Nicotiana
14.
Int J Cancer ; 137(3): 698-709, 2015 Aug 01.
Article in English | MEDLINE | ID: mdl-25557649

ABSTRACT

The tyrosine kinase inhibitor, imatinib, is the first line of treatment for chronic myeloid leukemia (CML) patients. Unfortunately, patients develop resistance and relapse due to bcr-abl point mutations and the persistence of leukemia initiating cells (LIC). Retinoids regulate vital biological processes such as cellular proliferation, apoptosis, and differentiation, in particular of hematopoietic progenitor cells. The clinical usage of natural retinoids is hindered by acquired resistance and undesirable side effects. However, bioavailable and less toxic synthetic retinoids, such as the atypical adamantyl retinoid ST1926, have been developed and tested in cancer clinical trials. We investigated the preclinical efficacy of the synthetic retinoid ST1926 using human CML cell lines and the murine bone marrow transduction/transplantation CML model. In vitro, ST1926 induced irreversible growth inhibition, cell cycle arrest and apoptosis through the dissipation of the mitochondrial membrane potential and caspase activation. Furthermore, ST1926 induced DNA damage and downregulated BCR-ABL. Most importantly, oral treatment with ST1926 significantly prolonged the longevity of primary CML mice, and reduced tumor burden. However, ST1926 did not eradicate LIC, evident by the ability of splenocytes isolated from treated primary mice to develop CML in untreated secondary recipients. These results support a potential therapeutic use of ST1926 in CML targeted therapy.


Subject(s)
Adamantane/analogs & derivatives , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cinnamates/pharmacology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Retinoids/pharmacology , Adamantane/administration & dosage , Adamantane/pharmacology , Administration, Oral , Animals , Antineoplastic Agents/administration & dosage , Caspases/metabolism , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cinnamates/administration & dosage , DNA Damage/drug effects , Disease Models, Animal , Dose-Response Relationship, Drug , Enzyme Activation/drug effects , Fusion Proteins, bcr-abl/metabolism , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality , Membrane Potential, Mitochondrial/drug effects , Mice , Reactive Oxygen Species/metabolism , Retinoids/administration & dosage , Signal Transduction/drug effects , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
15.
Tob Control ; 24 Suppl 1: i31-i43, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25661414

ABSTRACT

OBJECTIVE: It is widely held that waterpipe smoking (WPS) is not associated with health hazards. However, several studies have documented the uptake of several toxicants and carcinogens during WPS that is strongly associated with harmful health effects. This paper reviews the literature on the health effects of WPS. DATA SOURCES: Three databases-PubMed, MEDLINE and EMBASE-were searched until August 2014 for the acute and long-term health effects of WPS using the terms 'waterpipe' and its synonyms (hookah, shisha, goza, narghileh, arghileh and hubble-bubble) in various spellings. STUDY SELECTION: We included original clinical studies, case reports and systematic reviews and focused on clinical human studies. ∼10% of the identified studies met the selection criteria. DATA EXTRACTION: Data were abstracted by all three authors and summarised into tables. Abstracted data included study type, results and methodological limitations and were analysed jointly by all three authors. DATA SYNTHESIS: WPS acutely leads to increased heart rate, blood pressure, impaired pulmonary function and carbon monoxide intoxication. Chronic bronchitis, emphysema and coronary artery disease are serious complications of long-term use. Lung, gastric and oesophageal cancer are associated with WPS as well as periodontal disease, obstetrical complications, osteoporosis and mental health problems. CONCLUSIONS: Contrary to the widely held misconception, WPS is associated with a variety of adverse short-term and long-term health effects that should reinforce the need for stronger regulation. In addition, this review highlights the limitations of the published work, which is mostly cross-sectional or retrospective. Prospective studies should be undertaken to assess the full spectrum of health effects of WPS, particularly in view of its growing popularity and attractiveness to youth.


Subject(s)
Smoking/adverse effects , Cardiovascular Diseases/etiology , Female , Humans , Mouth Diseases/etiology , Neoplasms/etiology , Pregnancy , Pregnancy Outcome , Respiratory Tract Diseases/etiology , Water
16.
Tob Control ; 24(2): 125-7, 2015 Mar.
Article in English | MEDLINE | ID: mdl-23988862

ABSTRACT

BACKGROUND: In the past decade, waterpipe smoking-also known as hookah, shisha, narghileh-has increased among youth. The scarcity of rigorous studies linking waterpipe smoking to smoking-related diseases has hindered policy and regulatory efforts to confront the waterpipe epidemic. This study compares systemic carcinogen exposure between independent groups of exclusive waterpipe smokers, cigarette smokers and non-smokers. METHODS: This study was conducted at the Syrian Center for Tobacco Studies (SCTS) in Aleppo, Syria, between 2010 and 2011. First morning urinary samples were collected from three groups of subjects; exclusive daily waterpipe smokers (n=24), exclusive daily cigarette smokers (n=23), and non-smokers (n=28). These samples were analysed for carcinogenic tobacco-specific nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1- butanol (NNAL) using liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS: Our results show that waterpipe smokers are exposed to about 5-10 times greater NNAL than non-smokers. Mean (95% CI) free and total NNAL was 0.7 (0.3 to 1. 4) and 3.9 (1.6 to 9.5) pg/mL urine for non-smokers, 8.4 (4.8 to 14.8) and 33.0 (21.6 to 50.6) pg/mL urine for waterpipe smokers, and 10.7 (5.0 to 22.6) and 46.8 (27.6 to 79.3) pg/mL urine for cigarette smokers (p<0.001 for all comparisons). Daily waterpipe smokers were less exposed to NNAL than daily cigarette smokers, although the difference did not reach statistical significance for all measurements. CONCLUSIONS: These results provide the clearest indication to date about systemic exposure to harmful carcinogens associated with long-term waterpipe smoking. Such evidence can support policy and regulatory efforts designed to confront the emerging global waterpipe epidemic, as well as drive interventions aimed at increasing the public awareness about the cancer risk associated with waterpipe smoking.


Subject(s)
Air Pollution, Indoor/analysis , Carcinogens/analysis , Environmental Exposure/analysis , Nitrosamines/urine , Smoking/adverse effects , Tobacco Products/adverse effects , Tobacco Smoke Pollution/analysis , Adult , Female , Humans , Male , Neoplasms/etiology , Tobacco Products/classification , Tobacco Use Disorder/complications , Water , Young Adult
17.
J Med Genet ; 51(9): 623-34, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25097207

ABSTRACT

BACKGROUND: Hydatidiform mole (HM) is a human pregnancy with excessive trophoblastic proliferation and abnormal embryonic development that may be sporadic or recurrent. In the sporadic form, the HM phenotype is driven by an abnormal ratio of paternal to maternal genomes, whereas in the recurrent form, the HM phenotype is caused by maternal-recessive mutations, mostly in NLRP7, despite the diploid biparental origin of the HM tissues. In this study, we characterised the expression of the imprinted, maternally expressed gene, CDKN1C (p57(KIP2)), the genotype, and the histopathology of 36 products of conception (POC) from patients with two defective alleles in NLRP7 and looked for potential correlations between the nature of the mutations in the patients and the various HM features. METHODS/RESULTS: We found that all the 36 POCs are diploid biparental and have the same parental contribution to their genomes. However, some of them expressed variable levels of p57(KIP2) and this expression was strongly associated with the presence of embryonic tissues of inner cell mass origin and mild trophoblastic proliferation, which are features of triploid partial HMs, and were associated with missense mutations. Negative p57(KIP2) expression was associated with the absence of embryonic tissues and excessive trophoblastic proliferation, which are features of androgenetic complete HMs and were associated with protein-truncating mutations. CONCLUSIONS: Our data suggest that NLRP7, depending on the severity of its mutations, regulates the imprinted expression of p57(KIP2) and consequently the balance between tissue differentiation and proliferation during early human development. This role is novel and could not have been revealed by any other approach on somatic cells.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Cell Differentiation/physiology , Cell Proliferation/physiology , Cyclin-Dependent Kinase Inhibitor p57/metabolism , Gene Expression Regulation, Developmental/genetics , Hydatidiform Mole/genetics , Trophoblasts/physiology , Cell Differentiation/genetics , Cell Proliferation/genetics , Cyclin-Dependent Kinase Inhibitor p57/genetics , DNA Mutational Analysis , Female , Flow Cytometry , Genomic Imprinting/genetics , Genotype , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Microsatellite Repeats/genetics , Mutation, Missense/genetics , Pregnancy
18.
J Med Liban ; 63(4): 213-7, 2015.
Article in English | MEDLINE | ID: mdl-26821405

ABSTRACT

INTRODUCTION AND OBJECTIVES: The American University of Beirut Faculty of Medicine (AUB-FM) strategy is to develop faculty members (fm) skills by sponsoring local and international scientific activities has been in place for over three decades, and remains dependent on individuals' efforts. In 2011-2012, Faculty Development Program (FDP) was introduced to develop faculty leadership, business skills in medicine, fulfill personal and professional goals, followed by a five-year plan to cover five themes: Management/Leadership, Marketing, Finance, Strategic Planning and Communications with the purpose of integrating these themes in medical practice. METHODS: A survey was sent to all departments at AUB-FM in 2011 to assess needs and determine themes. Nine workshops were conducted, followed by post-workshop evaluation. RESULTS: 117 fm responded to needs assessment surveys. Respondents had on average 15 years in clinical practice, 50% with extensive to moderate administrative experience; 71% assumed administrative responsibilities at least once, 56% in leadership positions. Faculty attendance dropped midway from 69 to 19, although workshops were rated very good to excellent. DISCUSSION: Although faculty were interested in FDP, the drop in attendance might be attributed to: challenges to achieve personal and professional goals while struggling to fulfill their roles, satisfy promotion requirements and generate their income. RECOMMENDATIONS: FDP has to be aligned with FM strategic goals and faculty objectives, be complimentary to a faculty mentoring program, provide rewards, and be supported by a faculty progression tool.


Subject(s)
Faculty, Medical , Schools, Medical/organization & administration , Lebanon , Surveys and Questionnaires , United States
19.
Int J Cancer ; 134(4): 988-96, 2014 Feb 15.
Article in English | MEDLINE | ID: mdl-23934954

ABSTRACT

Imatinib is the standard of care in chronic meloid leukemia (CML) therapy. However, imatinib is not curative since most patients who discontinue therapy relapse indicating that leukemia initiating cells (LIC) are resistant. Interferon alpha (IFN) induces hematologic and cytogenetic remissions and interestingly, improved outcome was reported with the combination of interferon and imatinib. Arsenic trioxide was suggested to decrease CML LIC. We investigated the effects of arsenic and IFN on human CML cell lines or primary cells and the bone marrow retroviral transduction/transplantation murine CML model. In vitro, the combination of arsenic and IFN inhibited proliferation and activated apoptosis. Importantly, arsenic and IFN synergistically reduced the clonogenic activity of primary bone marrow cells derived from CML patients. Finally, in vivo, combined interferon and arsenic treatment, but not single agents, prolonged the survival of primary CML mice. Importantly, the combination severely impaired engraftment into untreated secondary recipients, with some recipients never developing the disease, demonstrating a dramatic decrease in CML LIC activity. Arsenic/IFN effect on CML LIC activity was significantly superior to that of imatinib. These results support further exploration of this combination, alone or with imatinib aiming at achieving CML eradication rather than long-term disease control.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Apoptosis , Cell Transformation, Neoplastic/drug effects , Interferon-alpha/pharmacology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Animals , Antiviral Agents/pharmacology , Arsenic Trioxide , Arsenicals/administration & dosage , Benzamides/administration & dosage , Bone Marrow Transplantation , Cell Transformation, Neoplastic/pathology , Humans , Imatinib Mesylate , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Mice , Mice, Inbred BALB C , Oxides/administration & dosage , Piperazines/administration & dosage , Prognosis , Pyrimidines/administration & dosage , Real-Time Polymerase Chain Reaction , Survival Rate , Tumor Cells, Cultured , Tumor Stem Cell Assay
20.
Int J Gynecol Pathol ; 33(3): 263-7, 2014 May.
Article in English | MEDLINE | ID: mdl-24681737

ABSTRACT

Alveolar soft part sarcoma of the vulvovaginal region is limited to only 8 reported vaginal cases and 1 vulvar case in the English literature. The histogenesis of the tumor remains intriguing with postulates favoring a myogenic versus nonmyogenic origin. A reciprocal translocation for ASPL-TFE3 gene fusion, frequently detected in ~90% of cases, combined with TFE3 protein immunoexpression are highly sensitive and specific methods for diagnostic confirmation. The current report describes a unique case of vulvovaginal alveolar soft part sarcoma showing the classic morphologic features with documentation of TFE3 protein expression and the ASPL-TFE3 gene rearrangement. Furthermore, a brief review of the literature of vulvar and vaginal alveolar soft part sarcoma cases with the various treatment modalities is outlined.


Subject(s)
Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics , Gene Expression Regulation, Neoplastic , Oncogene Proteins, Fusion/genetics , Sarcoma, Alveolar Soft Part/genetics , Vaginal Neoplasms/genetics , Vulvar Neoplasms/genetics , Female , Humans , Intracellular Signaling Peptides and Proteins , Sarcoma, Alveolar Soft Part/pathology , Translocation, Genetic , Vagina/pathology , Vaginal Neoplasms/pathology , Vulva/pathology , Vulvar Neoplasms/pathology , Young Adult
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