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BACKGROUND/AIMS: Many questions in cancer biology remain unanswered. Perhaps the most important issues remaining to be addressed focus on the molecular basis of carcinogenesis. Today's cancer focus lies on genetics and gene expression, which is unlikely to explain the true cause of most cancers or lead to a cure. METHODS: Earlier, we provided a plausible mechanism for this process, specifically, that most cancers develop in response to pathogenic stimuli that induce chronic inflammation, fibrosis, and remodeling of the cellular microenvironment. Collectively, these changes generate a precancerous niche (PCN) in which fibrosis and remodeling are ongoing secondary to persistent inflammation, followed by the deployment of a chronic stress escape strategy (CSES). If the CSES is unsuccessful, the cell undergoes a normal cell to cancer cell transformation (NCCT). RESULTS: Here, we highlight the critical role of fibroblasts as the first cells to undergo neoplastic transformation to a cancerous phenotype which is based on several critical findings. First, persistent disruption of homeostatic crosstalk increases lysyl oxidase activity and lysine oxidation which leads to increased collagen stiffness and decreased elasticity. If unresolved, chronic tissue stress will lead to an escape strategy that involves the recruitment of fibroblasts and fibrocytes from the bone marrow as well as cells undergoing an epithelial-mesenchymal transition (EMT). This yields a heterogeneous pool of cells that express both epithelial and mesenchymal markers and that will ultimately differentiate into cancer-associated fibroblasts (CAFs). Finally, CAFs undergo a mesenchymalepithelial transition (MET) and express epithelial markers that facilitate their integration into the target tissue. CONCLUSION: Here, we review the published findings that led us to this conclusion which is the most plausible answer to this critical question.
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Conhecimento , Neoplasias , Humanos , Fibroblastos/metabolismo , Neoplasias/patologia , Transição Epitelial-Mesenquimal/genética , Fibrose , Inflamação/patologia , Linhagem Celular Tumoral , Microambiente Tumoral/genéticaRESUMO
OBJECTIVES: This study explores trends in sex work among people who inject drugs (PWID) by gender and the relationship between sex work and adverse health outcomes including overdose, injection-site, and blood-borne virus (BBV) infections. STUDY DESIGN: The Unlinked Anonymous Monitoring Survey of PWID is an annual cross-sectional survey that monitors BBV prevalence and behaviours, including transactional sex, among PWID recruited through specialist services in England, Wales, and Northern Ireland. METHODS: Trends in sex work among PWID (2011-2021) were described. Data were analysed to assess differences between PWID who engaged in sex work in the past year (sex workers [SWs]) and those who did not (non-SWs) by gender (Pearson Chi2 tests) (2018-2021). Associations between sex work in the past year and adverse health outcomes were investigated using logistic regression. RESULTS: Between 2011 and 2021, sex work among PWID remained stable, with 31% of women and 6.3% of men who inject, reporting having ever engaged in sex work, and 14% of women and 2.2% of men engaging in sex work in the past year. Between 2018 and 2021, SWs had greater odds of reporting symptoms of an injection-site infection (adjusted odds ratio (aOR): 1.68 [95% confidence interval {CI}: 1.31-2.16], P < 0.001) and reporting overdose (aOR: 2.21 [CI: 1.74-2.80], P < 0.001) than non-SWs had in the past year. Among men, SWs had 243% greater odds of having HIV than non-SWs (aOR: 3.43 [CI: 1.03-11.33], P = 0.043). CONCLUSIONS: Our findings highlight disproportionate vulnerability and intersection of overlapping risk factors experienced by PWID SWs and a need for tailored interventions which are inclusive and low-threshold.
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Overdose de Drogas , Usuários de Drogas , Infecções por HIV , Abuso de Substâncias por Via Intravenosa , Masculino , Humanos , Feminino , Trabalho Sexual , Abuso de Substâncias por Via Intravenosa/epidemiologia , Estudos Transversais , Overdose de Drogas/epidemiologia , Avaliação de Resultados em Cuidados de Saúde , Infecções por HIV/epidemiologia , Assunção de Riscos , PrevalênciaRESUMO
The present study analyzes the theoretical consequences of slip effects in a complex stenosed region. The flow of blood in a stenosed region is incorporated with hybrid nanofluid features which are being prepared with copper and copper oxide nanoparticles. The flow is also intensified by applying an electric field in the axial direction. The governing equations for the proposed paradigm are solved and the corresponding closed-form solutions are obtained for the cases of mild stenosis. Parameters such as Electro-osmotic, velocity slip and Helmholtz-Smoluchowski are specially focused in this study. The heat transfer, hemodynamic velocity, wall shear stress and resistance impedance for the flow are precisely determined. The various parameters that influence the physical characteristics of flow are plotted, and their effects are discussed in detail. The present model has the potential application in medical pumps for drug delivery systems.
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Cobre , Hemodinâmica , Humanos , Constrição Patológica , Eletro-Osmose , Sistemas de Liberação de MedicamentosRESUMO
In this analysis, we explore a nanofluid model that represents the role of ciliary carpets in the transport of magnetohydrodynamic fluid in an electroosmotic channel. Hybrid nanofluid features are also taken into interpretation. The equations leading the flow analysis are converted into non-dimensional form by supposing long wavelength and low Reynolds number approximations. Analytical solutions for velocity distribution, pressure gradient and stream function are acquired and solved by a mathematic solver. The effects of the relevant physical parameters are graphically noted. The consequence of the present model has remarkable applications, which can be used in various areas of biological transport processes, artificial cilia design and in the operation of other mechanical devices.
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Summary: A 44-year-old athletic man presented in 2009 with severe low back pain. Dual-energy x-ray absorptiometry revealed severe osteoporosis; serum testosterone was 189 ng/dL while serum estradiol (E2) measured by liquid chromatography/mass spectrometry was 8 pg/mL. DNA was extracted and sequenced from a blood sample from the patient since his maternal first cousin also had low bone mass and both patients were screened for aromatase dysfunction by PCR analysis for the CYP19A1 gene, which encodes aromatase. No known pathologic mutations were observed in the coding exons, but novel single nucleotide polymorphisms were detected both in the proband and in his cousin. Treatment with topical testosterone started in August 2010. Over the next 8 years, testosterone dosage was varied and switched from topical gel to injections and maintained on depo-injections of testosterone at about 60 mg once per week. Re-examination in March 2012 included a brain MRI to exclude pituitary lesions; hyperparathyroidism was ruled out (normal serum parathyroid hormone, calcium, and calcium to phosphorous ratio) and celiac disease was excluded (negative transglutaminase antibodies). Follow-up in October 2018 showed improved bone mineral density of the lumbar spine by 29% and of the left femoral hip by 15% compared to baseline measurements. This reveals the importance of measuring serum E2 for making the correct diagnosis, as well as for monitoring a therapeutic effect. Herein, we propose treatment of male osteoporosis where serum E2 levels are below about 20 pg/mL with testosterone to reverse osteoporosis. Learning points: Estrogen deficiency in the diagnosis of male idiopathic osteoporosis. Importance of serum estradiol in male osteoporosis. Role of polymorphisms in aromatase gene on bone health. Reversal of osteoporosis. Tailored testosterone treatment for bone health.
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Radioactivity and radiation-induced mutations are believed to be primary causal examples of cancer-initiating events (stimulus). The assumption that an increase in cancer risk develops from any amount of radiation gave rise to the linear no-threshold model. This also led to the assumption that cancer is caused by somatic mutations as described by the somatic mutation theory. Against this backdrop, in actuality only ~5%-10% of cancers result from somatic mutations or its various modifications, while ~80% of cancers are still termed as 'sporadic', meaning that their cause is unknown. Therefore, both the linear no-threshold model and the somatic mutation theory have resulted in an incongruity in thinking. Decades of molecular and clinical research since 2012 led to the development of the cancer paradigm, "Epistemology of the origin of cancer", which explains why the majority of cancers originate as a result of a sixstep sequence of events. An understanding of the essentials of physics helps to explain the interconnections between physics and the biology of cancer. This allows for a much-needed reconciliation of past errors and leads to a deeper understanding of carcinogenesis.
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Conhecimento , Neoplasias , Carcinogênese/genética , Humanos , Mutação , Neoplasias/genética , FísicaRESUMO
SUMMARY: In this paper we build on work investigating the feasibility of human immunodeficiency virus (HIV) testing in emergency departments (EDs), estimating the prevalence of hepatitis B, C and HIV infections among persons attending two inner-London EDs, identifying factors associated with testing positive in an ED. We also undertook molecular characterisation to look at the diversity of the viruses circulating in these individuals, and the presence of clinically significant mutations which impact on treatment and control.Blood-borne virus (BBV) testing in non-traditional settings is feasible, with emergency departments (ED) potentially effective at reaching vulnerable and underserved populations. We investigated the feasibility of BBV testing within two inner-London EDs. Residual samples from biochemistry for adults (⩾18 years) attending The Royal Free London Hospital (RFLH) or the University College London Hospital (UCLH) ED between January and June 2015 were tested for human immunodeficiency virus (HIV)Ag/Ab, anti-hepatitis C (HCV) and HBsAg. PCR and sequence analysis were conducted on reactive samples. Sero-prevalence among persons attending RFH and UCLH with residual samples (1287 and 1546), respectively, were 1.1% and 1.0% for HBsAg, 1.6% and 2.3% for anti-HCV, 0.9% and 1.6% for HCV RNA, and 1.3% and 2.2% for HIV. For RFH, HBsAg positivity was more likely among persons of black vs. white ethnicity (odds ratio 9.08; 95% confidence interval 2.72-30), with anti-HCV positivity less likely among females (0.15, 95% CI 0.04-0.50). For UCLH, HBsAg positivity was more likely among non-white ethnicity (13.34, 95% CI 2.20-80.86 (Asian); 8.03, 95% CI 1.12-57.61 (black); and 8.11, 95% CI 1.13-58.18 (other/mixed)). Anti-HCV positivity was more likely among 36-55 year olds vs. ⩾56 years (7.69, 95% CI 2.24-26.41), and less likely among females (0.24, 95% CI 0.09-0.65). Persons positive for HIV-markers were more likely to be of black vs. white ethnicity (4.51, 95% CI 1.63-12.45), and less likely to have one ED attendance (0.39, 95% CI 0.17-0.88), or female (0.12, 95% CI 0.04-0.42). These results indicate that BBV-testing in EDs is feasible, providing a basis for further studies to explore provider and patient acceptability, referral into care and cost-effectiveness.
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Anticorpos Anti-HIV/sangue , Antígenos HIV/sangue , Infecções por HIV/epidemiologia , Antígenos de Superfície da Hepatite B/sangue , Hepatite B/epidemiologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Serviço Hospitalar de Emergência , Feminino , Genótipo , HIV/classificação , HIV/genética , HIV/imunologia , Hepacivirus/classificação , Hepacivirus/genética , Hepacivirus/imunologia , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hospitais , Humanos , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto JovemRESUMO
Melasma is a common, therapeutically challenging, and universally relapsing disorder of hyperpigmentation that is most often observed in women and individuals with Fitzpatrick Skin Types III through VI. The pathogenesis of melasma is complex and protean. Contributing factors that are often implicated in the etiopathogenesis of this condition include a genetic predisposition, intense ultraviolet radiation exposure, and hormonal influences. Therapeutic interventions for melasma include a multimodality approach incorporating photoprotection agents, topical and oral skin lighteners, and resurfacing procedures. Given our expanding knowledge of the pathogenesis of melasma, new and effective treatments are expanding our therapeutic armamentarium. This article reviews new and emerging oral and topical treatments for melasma.
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There is increasing interest in the influence of place on health, and the need to distinguish between environmental and individual level factors. For environmental-level factors, current evidence tends to show associations through cross-sectional and uncontrolled longitudinal analyses rather than through more robust study designs that can provide stronger causal evidence. We restricted this systematic review to randomised (or cluster) randomised controlled trials and controlled before-and-after studies of changes to the built environment. Date of search was December 2016. We identified 14 studies. No evidence was found of an effect on mental health from 'urban regeneration' and 'improving green infrastructure' studies. Beneficial effects on quality-of-life outcomes from 'improving green infrastructure' were found in two studies. One 'improving green infrastructure' study reported an improvement in social isolation. Risk-of-bias assessment indicated robust data from only four studies. Overall, evidence for the impact of built environment interventions on mental health and quality-of-life is weak. Future research requires more robust study designs and interdisciplinary research involving public health, planning and urban design experts.
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Ambiente Construído , Planejamento Ambiental , Saúde Mental , Adulto , Humanos , Qualidade de Vida , População UrbanaRESUMO
BACKGROUND: Hepatitis E virus (HEV) is an important infectious agent causing acute and chronic disease. Chronic hepatitis E affects immunocompromised people and serological testing is neither reliable nor sufficient to infer whether a patient has infection; therefore HEV RNA testing is the only reliable diagnostic test presently available. An HEV antigen-specific ELISA test is commercially available but is not yet in clinical use. OBJECTIVES: 1) determine the prevalence of HEV infection in the Royal Free Hospital (RFH) liver transplant cohort; 2) compare the diagnostic utility of HEV antigen-detection against the current gold standard; 3) consider screening strategies for HEV infection in immunocompromised groups. STUDY DESIGN: The serum samples of 490 post liver transplant patients visiting the outpatient clinic at the RFH over an eight-month period were tested for HEV with both an HEV antigen-specific ELISA and HEV RNA test. RESULTS: The prevalence of HEV infection was 0.20% (95% CI 0.0%-1.1%). The specificity of the ELISA was 98.2% with a positive predictive value of 10.0%. There was one true positive HEV case, which was picked up correctly by the antigen-specific ELISA. These results were improved by incorporating a neutralisation step into further ELISA tests. CONCLUSIONS: The antigen-specific ELISA test gave no false negative results, supporting its utility as a screening tool. There was one true antigen positive result. Further investigation including cost analysis is indicated to determine the efficacy of HEV antigen-specific ELISA testing in a screening context and in the clinical investigation of HEV infection in immunocompromised patients.
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Ensaio de Imunoadsorção Enzimática , Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/genética , Hepatite E/diagnóstico , Reação em Cadeia da Polimerase , Adolescente , Adulto , Estudos de Coortes , Feminino , Antígenos de Hepatite/sangue , Hepatite E/sangue , Hepatite E/imunologia , Hospitais Universitários , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , RNA Viral , Transplantados , Adulto JovemRESUMO
Hepatitis E virus genotype 1 (HEV G1) is an important cause of morbidity and mortality in Africa and Asia. HEV G1's natural history, including the incubation period, remains poorly understood, hindering surveillance efforts and effective control. Using individual-level data from 85 travel-related HEV G1 cases in England and Wales, we estimate the incubation period distribution using survival analysis methods, which allow for appropriate inference when only time ranges, rather than exact times are known for the exposure to HEV and symptom onset. We estimated a 29.8-day (95% confidence interval (CI) 24.1-36.0) median incubation period with 5% of people expected to develop symptoms within 14.3 days (95% CI 10.1-21.7) and 95% within 61.9 days (95% CI 47.4-74.4) of exposure. These estimates can help refine clinical case definitions and inform the design of disease burden and intervention studies.
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Hepatite E/genética , Período de Incubação de Doenças Infecciosas , Viagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Inglaterra/epidemiologia , Feminino , Genótipo , Hepatite E/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , País de Gales/epidemiologiaRESUMO
Lookback was initiated upon notification of an acute HBV infection in a repeat Irish donor, 108 days post-donation. The donation screened non-reactive by individual-donation nucleic acid testing (ID-NAT) using the Procleix Ultrio Elite multiplex assay and again when the archived sample was retested, but the discriminatory assay for HBV was reactive. The immunocompromised recipient of the implicated red cell component was tested 110 days post-transfusion, revealing a HBV DNA viral load of 470 IU/ml. Genotype C2 sequences identical across two regions of the HBV genome were found in samples from the donor and recipient.
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Genótipo , Vírus da Hepatite B/genética , Hepatite B/transmissão , Reação Transfusional/epidemiologia , Doadores de Sangue , Genoma Viral , Hepatite B/sangue , Hepatite B/epidemiologia , Humanos , Reação Transfusional/sangueRESUMO
Genotype 3 hepatitis E virus (HEV) can lead to persistent infections in immunocompromised hosts. A recently available commercial assay for the detection of HEV antigen (HEV-Ag ELISA, Wantai diagnostics) may enable the study of HEV-Ag dynamics in such persistent infections, however currently there is no confirmatory test available. We generated a putative neutralising reagent from a pool of four convalescent blood donor samples and explored neutralising activity against HEV antigens from clinical samples, HEV tissue-culture and virus-like particles. Using this neutralisation method we were able to differentiate true reactivity from non-specific reactivity in plasma, stool and urine samples. This could also facilitate the introduction of HEV-Ag detection as a screening assay or the study of HEV-Ag in different body fluids.
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Ensaio de Imunoadsorção Enzimática , Antígenos E da Hepatite B/isolamento & purificação , Hepatite E/diagnóstico , Fezes/virologia , Anticorpos Anti-Hepatite/sangue , Hepatite E/imunologia , Vírus da Hepatite E , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Testes de Neutralização , RNA Viral/genética , Kit de Reagentes para Diagnóstico , Sensibilidade e EspecificidadeRESUMO
Little is known about engagement and retention in care of people diagnosed with chronic hepatitis C (HCV) in England. Establishing a cascade of care informs targeted interventions for improving case finding, referral, treatment uptake and retention in care. Using data from the sentinel surveillance of blood-borne virus (SSBBV) testing between 2005 and 2014, we investigate the continuum of care of those tested for HCV in England. Persons ≥1 year old with an anti-HCV test and subsequent RNA tests between 2005 and 2014 reported to SSBBV were collated. We describe the cascade of care, as the patient pathway from a diagnostic test, referral into care, treatment and patient outcomes. Between 2005 and 2014, 2 390 507 samples were tested for anti-HCV, corresponding to 1 766 515 persons. A total of 53 038 persons (35 190 men and 17 165 women) with anti-HCV positive were newly reported to SSBBV. An RNA test was conducted on 77.0% persons who were anti-HCV positive, 72.3% of whom were viraemic (RNA positive) during this time period, 21.4% had evidence of treatment and 3130 49.5% had evidence of a sustained virological response (SVR). In multivariable models, confirmation of viraemia by RNA test varied by age and region/test setting; evidence of treatment varied by age, year of test and region/test setting; and SVR varied by age, year of test and region/setting of test. In conclusion, our findings provide HCV cascade of care estimates prior to the introduction of direct acting antivirals. These findings provide important baseline cascade estimates to benchmark progress towards elimination of HCV as a major public health threat.
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Antivirais/uso terapêutico , Continuidade da Assistência ao Paciente/organização & administração , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Benchmarking , Criança , Pré-Escolar , Inglaterra , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto JovemRESUMO
Indigenous, foodborne transmission of hepatitis E has been increasing across industrialised countries. Public Health England has conducted enhanced surveillance in England and Wales since 2003.This report gives an account of acute infections from 2010 to 2016 and describes modification made to the methods of surveillance to account for changes in reporting behaviours and improve ascertainment.
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Hepatite E/epidemiologia , Armazenamento e Recuperação da Informação , Vigilância da População/métodos , Notificação de Doenças , Inglaterra/epidemiologia , Humanos , Incidência , País de Gales/epidemiologiaRESUMO
Since 2010, human hepatitis E infections have increased in England and Wales. Most cases are locally acquired and caused by hepatitis E virus genotype 3 (HEV G3). HEV G3 is linked to the consumption of pork products. The increase is associated with the emergence of a new phylotype, HEV G3-group 2 (G3-2, also known as G3abcdhij). Sixty individuals with confirmed hepatitis E infection and no history of travel outside the UK were recruited: 19 were infected with HEV G3-group 1 (G3-1 or G3efg) and 41 with G3-2. Epidemiological data relating to usual shopping habits and consumption of ham and sausages were analysed together with typing data to identify any associations with HEV phylotype. Study participants who purchased ham and/or sausage from a major supermarket were more likely to have HEV G3-2 infection (Relative risks 1·85, P = 0·06, CI 0·97-3·53). The HEV G3-2 phylotype has not been detected in indigenous UK pigs and it is suggested that human infections could be the result of consumption of products made from pork originating outside the UK. This does not infer blame on the supermarket but the epidemiology of HEV is dynamic and reflects complex animal husbandry practices which need to be explored further.
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Vírus da Hepatite E/fisiologia , Hepatite E/epidemiologia , Produtos da Carne/virologia , Carne Vermelha/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Coortes , Inglaterra/epidemiologia , Feminino , Hepatite E/virologia , Vírus da Hepatite E/genética , Humanos , Masculino , Pessoa de Meia-Idade , Sus scrofa , País de Gales/epidemiologia , Adulto JovemRESUMO
Hepatitis E virus (HEV) infection is a major cause of acute hepatitis worldwide. This infection causes major water-borne outbreaks in low- and middle-income countries, whilst in industrialised countries this infection is zoonotic. These differences in epidemiology are related to different HEV genotypes. HEV genotype 3 is a zoonotic infection, whilst genotype 2 causes large outbreaks. This study determined the seroprevalence of HEV in blood donors from the Western Cape. Anti-hepatitis A virus (anti-HAV) antibody was detected in 184/300 (61%) donors. Antibody to HEV (anti-HEV) was detected in 78 of 300 donors (26%). It was highest in mixed race donors (62/100), followed by white donors (23/100) and lowest in black donors (19/100) P = 0.019. Since it is thought that genotypes 1 and 2 predominate both viruses would be acquired by the oro-faecal route, it is surprising that HEV seroprevalence does not mirror that of HAV. We postulate that this may reflect differences in socio-economic status and consumption of dietary meat. So the marked divergence between HEV and HAV seroprevalence may be the result of different routes of transmission. Further data are needed to explore the risk factors associated with HEV infection.
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Doadores de Sangue , Genótipo , Vírus da Hepatite A/imunologia , Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/imunologia , Adolescente , Adulto , Idoso , Feminino , Hepatite A/epidemiologia , Hepatite A/virologia , Vírus da Hepatite A/genética , Hepatite E/epidemiologia , Hepatite E/virologia , Vírus da Hepatite E/genética , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Soroepidemiológicos , África do Sul/epidemiologia , Adulto JovemRESUMO
In this paper, we have discussed the influence of copper nanoparticles on a blood flow through composite stenosed artery with permeable walls. The nature of blood is discussed mathematically by considering it as viscous nanofluid. The study is carried out for a blood vessel under mild stenosis approximations and expressions of the temperature, velocity, resistance impedance to flow, wall shear stress and the pressure gradient is obtained by using corresponding boundary conditions. Results for the effects of permeability on blood flow through composite stenosis have been discussed graphically. The considered analysis also summarizes that the drug copper nanoparticles are efficient to reduce hemodynamics of stenosis and could be helpful to predict important uses for biomedical applications. Results indicate that nanoparticles are helpful as drug carriers to minimize the effects of resistance impedance to blood flow or coagulation factors due to stenosis.
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Artérias/fisiologia , Constrição Patológica , Portadores de Fármacos , Nanopartículas , Fluxo Sanguíneo Regional , Modelos Cardiovasculares , PermeabilidadeRESUMO
Hysteron proteron reverses both temporal and logical order and this syllogism occurs in carcinogenesis and the somatic mutation theory (SMT): the first (somatic mutation) occurs only after the second (onset of cancer) and, therefore, observed somatic mutations in most cancers appear well after the early cues of carcinogenesis are in place. It is no accident that mutations are increasingly being questioned as the causal event in the origin of the vast majority of cancers as clinical data show little support for this theory when compared against the metrics of patient outcomes. Ever since the discovery of the double helical structure of DNA, virtually all chronic diseases came to be viewed as causally linked to one degree or another to mutations, even though we now know that genes are not simply blueprints, but rather an assemblage of alphabets that can, under non-genetic influences, be used to assemble a business letter or a work of Shakespearean literature. A minority of all cancers is indeed caused by mutations but the SMT has been applied to all cancers, and even to chemical carcinogenesis, in the absence of hard evidence of causality. Herein, we review the 100 year story of SMT and aspects that show why genes are not just blueprints, how radiation and mutation are associated in a more nuanced view, the proposed risk of cancer and bad luck, and the in vitro and in vivo evidence for a new cancer paradigm. This paradigm is scientifically applicable for the majority of non-heritable cancers and consists of a six-step sequence for the origin of cancer. This new cancer paradigm proclaims that somatic mutations are epiphenomena or later events occurring after carcinogenesis is already underway. This serves not just as a plausible alternative to SMT and explains the origin of the majority of cancers, but also provides opportunities for early interventions and prevention of the onset of cancer as a disease.
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Modelos Teóricos , Neoplasias/patologia , Carcinogênese/genética , Transformação Celular Neoplásica , Dano ao DNA/efeitos da radiação , Humanos , Inflamação , Mutação , Neoplasias/genética , Neoplasias/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismoRESUMO
One major objective for our evolving understanding in the treatment of cancers will be to address how a combination of diagnosis and treatment strategies can be used to integrate patient and tumor variables with an outcome-oriented approach. Such an approach, in a multimodal therapy setting, could identify those patients (1) who should undergo a defined treatment (personalized therapy) (2) in whom modifications of the multimodal therapy due to observed responses might lead to an improvement of the response and/or prognosis (individualized therapy), (3) who might not benefit from a particular toxic treatment regimen, and (4) who could be identified early on and thereby be spared the morbidity associated with such treatments. These strategies could lead in the direction of precision medicine and there is hope of integrating translational molecular data to improve cancer classifications. In order to achieve these goals, it is necessary to understand the key issues in different aspects of biotechnology to anticipate future directions of personalized and individualized diagnosis and multimodal treatment strategies. Providing an overview of translational data in cancers proved to be a challenge as different methods and techniques used to obtain molecular data are used and studies are based on different tumor entities with different tumor biology and prognoses as well as vastly different therapeutic approaches. The pros and cons of the available methodologies and the potential response data in genomics, microRNA, epigenetics and proteomics with a focus on upper gastrointestinal cancers are considered herein to allow for an understanding of where these technologies stand with respect to cancer diagnosis, prognosis and treatment.