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1.
Cell Physiol Biochem ; 57(6): 512-537, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38149603

RESUMO

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.


Assuntos
Conhecimento , Neoplasias , Humanos , Fibroblastos/metabolismo , Neoplasias/patologia , Transição Epitelial-Mesenquimal/genética , Fibrose , Inflamação/patologia , Linhagem Celular Tumoral , Microambiente Tumoral/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-37073856

RESUMO

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.

3.
Cell Physiol Biochem ; 56(5): 546-572, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36177655

RESUMO

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.


Assuntos
Conhecimento , Neoplasias , Carcinogênese/genética , Humanos , Mutação , Neoplasias/genética , Física
4.
Cell Physiol Biochem ; 38(5): 1663-80, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27160408

RESUMO

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.


Assuntos
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/metabolismo
5.
Clin Transl Med ; 5(1): 13, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27053248

RESUMO

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.

6.
Pediatr Dermatol ; 32(3): e124-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25780817

RESUMO

Acrodermatitis enteropathica (AE) is a rare disease that results from a defective gene, SLC39A4, and is characterized by dermatitis, alopecia, and diarrhea. We report a case of AE presenting with only periorificial and acral dermatitis in which genetic testing revealed two novel compound heterozygous missense mutations for SLC39A4. This case demonstrates that not all AE mutations alter zinc transporters in the same manner and highlights the phenotypic variability of AE.


Assuntos
Acrodermatite/tratamento farmacológico , Acrodermatite/genética , Proteínas de Transporte de Cátions/genética , Zinco/deficiência , Zinco/uso terapêutico , Criança , Humanos , Masculino , Mutação
7.
Cell Physiol Biochem ; 34(2): 213-43, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25034869

RESUMO

The delineation of key molecular pathways has enhanced our knowledge of the biology of tumor microenvironment, tumor dissemination, and carcinogenesis. The complexities of cell-cell communication and the possibilities for modulation provide new opportunities for treating cancers. Cells communicate by direct and indirect signaling. Direct cell-cell communication involves both, self-self-communication (intracrine and autocrine), and adjacent communication with nearby cells (juxtacrine), which themselves are regulated by distinct pathways. Indirect intercellular communication involves local communication over short distances (paracrine and synaptic signaling) or over large distances via hormones (endocrine). The essential components of cell-cell communication involve communication junctions (Connexins, Plasmodesmata, Ion Channels, Chemical Synapses, and Pannexins), occluding junctions (Tight Junctions), and anchoring junctions (Adherens, Desmosomes, Focal Adhesions, and Hemidesmosomes). The communication pathways pass through junctions at physical cell-cell attachments, and they go, as well, through the extracellular matrix (ECM) via the different transmembrane adhesion proteins (Cadherins and Integrins). We have here reviewed cell-cell communication involving (1) the components of junctions and their dynamic interplay with the other aspects of communication, including (2) the tumor microenvironment and carcinogenesis, (3) coupling and migration, (4) the underlying cell-cell and sub-cellular communication mechanisms (signaling) of anticancer treatments, and finally, (5) aspects of recent research on cell-cell communication.


Assuntos
Antineoplásicos/uso terapêutico , Carcinogênese , Comunicação Celular , Microambiente Tumoral , Humanos
8.
BMC Cancer ; 14: 331, 2014 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-24885752

RESUMO

BACKGROUND: Carcinogenesis is widely thought to originate from somatic mutations and an inhibition of growth suppressors, followed by cell proliferation, tissue invasion, and risk of metastasis. Fewer than 10% of all cancers are hereditary; the ratio in gastric (1%), colorectal (3-5%) and breast (8%) cancers is even less. Cancers caused by infection are thought to constitute some 15% of the non-hereditary cancers. Those remaining, 70 to 80%, are called "sporadic," because they are essentially of unknown etiology. We propose a new paradigm for the origin of the majority of cancers. PRESENTATION OF HYPOTHESIS: Our paradigm postulates that cancer originates following a sequence of events that include (1) a pathogenic stimulus (biological or chemical) followed by (2) chronic inflammation, from which develops (3) fibrosis with associated changes in the cellular microenvironment. From these changes a (4) pre-cancerous niche develops, which triggers the deployment of (5) a chronic stress escape strategy, and when this fails to resolve, (6) a transition of a normal cell to a cancer cell occurs. If we are correct, this paradigm would suggest that the majority of the findings in cancer genetics so far reported are either late events or are epiphenomena that occur after the appearance of the pre-cancerous niche. TESTING THE HYPOTHESIS: If, based on experimental and clinical findings presented here, this hypothesis is plausible, then the majority of findings in the genetics of cancer so far reported in the literature are late events or epiphenomena that could have occurred after the development of a PCN. Our model would make clear the need to establish preventive measures long before a cancer becomes clinically apparent. Future research should focus on the intermediate steps of our proposed sequence of events, which will enhance our understanding of the nature of carcinogenesis. Findings on inflammation and fibrosis would be given their warranted importance, with research in anticancer therapies focusing on suppressing the PCN state with very early intervention to detect and quantify any subclinical inflammatory change and to treat all levels of chronic inflammation and prevent fibrotic changes, and so avoid the transition from a normal cell to a cancer cell. IMPLICATION OF THE HYPOTHESIS: The paradigm proposed here, if proven, spells out a sequence of steps, one or more of which could be interdicted or modulated early in carcinogenesis to prevent or, at a minimum, slow down the progression of many cancers.


Assuntos
Transformação Celular Neoplásica , Neoplasias/etiologia , Lesões Pré-Cancerosas/etiologia , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Fibrose , Predisposição Genética para Doença , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Fatores de Risco , Transdução de Sinais , Microambiente Tumoral
9.
BMC Cancer ; 14: 186, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24629025

RESUMO

BACKGROUND: Since the "War on Cancer" was declared in 1971, the United States alone has expended some $300 billion on research, with a heavy focus on the role of genomics in anticancer therapy. Voluminous data have been collected and analyzed. However, in hindsight, any achievements made have not been realized in clinical practice in terms of overall survival or quality of life extended. This might be justified because cancer is not one disease but a conglomeration of multiple diseases, with widespread heterogeneity even within a single tumor type. DISCUSSION: Only a few types of cancer have been described that are associated with one major signaling pathway. This enabled the initial successful deployment of targeted therapy for such cancers. However, soon after this targeted approach was initiated, it was subverted as cancer cells learned and reacted to the initial treatments, oftentimes rendering the treatment less effective or even completely ineffective. During the past 30 plus years, the cancer classification used had, as its primary aim, the facilitation of communication and the exchange of information amongst those caring for cancer patients with the end goal of establishing a standardized approach for the diagnosis and treatment of cancers. This approach should be modified based on the recent research to affect a change from a service-based to an outcome-based approach. The vision of achieving long-term control and/or eradicating or curing cancer is far from being realized, but not impossible. In order to meet the challenges in getting there, any newly proposed anticancer strategy must integrate a personalized treatment outcome approach. This concept is predicated on tumor- and patient-associated variables, combined with an individualized response assessment strategy for therapy modification as suggested by the patient's own results. As combined strategies may be outcome-orientated and integrate tumor-, patient- as well as cancer-preventive variables, this approach is likely to result in an optimized anticancer strategy. SUMMARY: Herein, we introduce such an anticancer strategy for all cancer patients, experts, and organizations: Imagine a World without Cancer.


Assuntos
Detecção Precoce de Câncer , Neoplasias/diagnóstico , Neoplasias/terapia , Medicina de Precisão , Protocolos Antineoplásicos , Terapia Combinada , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/tendências , Humanos , Neoplasias/patologia , Medicina de Precisão/métodos , Medicina de Precisão/tendências
10.
DNA Repair (Amst) ; 10(7): 792-7, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21570926

RESUMO

The past two decades of research into Xeroderma pigmentosum (XP), an autosomal recessive disease, has been marked by significant progress in understanding the molecular basis of this rare disease. More importantly, especially from the perspective of the affected families, is that this knowledge has been applied to diagnose the condition both in utero as well as in the very early days of life. The eight known XP genes and their different phenotypes present a number of challenges that the XP Workshop sponsored by the NIH in 2010 has highlighted. There is little current treatment specifically designed for any of the XP types other than standard dermatological and neurological evaluations and care. The Xeroderma Pigmentosum Family Support Group (XPFSG) is dedicated to serving families with children and adults with all forms of XP and to help them better understand the condition, to identify practical measures which can be taken by the XP patients and their families to mitigate the effects of the disease, and to serve as patient advocates to help families discuss issues with their physicians. We summarize our efforts in terms of outreach within the US and abroad to affected families and discuss XPFSG-sponsored clinical initiatives that include molecular diagnoses, treatment, and initial proof-of-concept studies that can, if successful, improve the lives of XP patients in the near term.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Grupos de Autoajuda/organização & administração , Xeroderma Pigmentoso/prevenção & controle , Adolescente , Adulto , Criança , Pré-Escolar , Diterpenos , Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Raras/prevenção & controle , Doenças Raras/terapia , Ésteres de Retinil , Selênio/uso terapêutico , Protetores Solares/efeitos adversos , Raios Ultravioleta , Vitamina A/efeitos adversos , Vitamina A/análogos & derivados , Vitamina D/uso terapêutico , Xeroderma Pigmentoso/terapia , Adulto Jovem
11.
World J Gastroenterol ; 14(43): 6627-31, 2008 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-19034963

RESUMO

Over the past decade, significant improvements have been made in the treatment of chronic hepatitis C (CHC), especially with the introduction of combined therapy using both interferon and ribavarin. The optimal dose and duration of treatment is still a matter of debate and, importantly, the efficacy of this combined treatment varies with the viral genotype responsible for infection. In general, patients infected with viral genotypes 2 or 3 more readily achieve a sustained viral response than those infected with viral genotype 1. The introduction of a pegylated version of interferon in the past decade has produced better clinical outcomes in patients infected with viral genotype 1. However, the published literature shows no improvement in clinical outcomes in patients infected with viral genotypes 2 or 3 when they are treated with pegylated interferon as opposed to non-pegylated interferon, both given in combination with ribavarin. This is significant because the cost of a 24-wk treatment with pegylated interferon in less-developed countries is between six and 30 times greater than that of treatment with interferon. Thus, clinicians need to carefully consider the cost-versus-benefit of using pegylated interferon to treat CHC, particularly when there is no evidence for clinically measurable benefits in patients with genotypes 2 and 3 infections.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Genótipo , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Interferons/uso terapêutico , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes , Ribavirina/uso terapêutico
12.
J Environ Monit ; 10(2): 176-87, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18246211

RESUMO

This article questions the basis for benzene as the carcinogenic surrogate in deriving health risk-based 'clean-up levels' for gasoline-impacted soil and groundwater at leaking underground storage tank properties. The epidemiological evidence suggests that acute myelogenous leukemia (AML) associated with chronic occupational benzene exposure can be best described by sigmoid dose-response relationships. A review of the molecular toxicology and kinetics of benzene points to the existence of threshold mechanisms in the induction of leukemia. The toxicological and epidemiological literature on chronic exposure to unleaded gasoline indicates that the benzene exposures required to induce a measurable carcinogenic response are substantially greater than exposures likely to be encountered from exposure to gasoline at contaminated properties. Thus, assuming that theoretical cancer risks associated with exposure to benzene from gasoline reflect actual health risks associated with such environmental exposures to gasoline and using these theoretical cancer risks and cancer potency factors for benzene to dictate soil and groundwater clean up of gasoline are not scientifically defensible.


Assuntos
Benzeno/intoxicação , Benzeno/toxicidade , Carcinógenos Ambientais/intoxicação , Carcinógenos Ambientais/toxicidade , Gasolina/intoxicação , Gasolina/toxicidade , Animais , Humanos , Leucemia Mieloide Aguda/induzido quimicamente , Leucemia Mieloide Aguda/epidemiologia , Poluentes do Solo/intoxicação , Poluentes do Solo/toxicidade , Estados Unidos/epidemiologia , Poluentes Químicos da Água/intoxicação , Poluentes Químicos da Água/toxicidade
13.
Biol Trace Elem Res ; 114(1-3): 93-105, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17205991

RESUMO

We report on the successful use of repeated hair analyses over three decades to monitor zinc and copper status in two siblings with Acrodermatitis enteropathica who were treated with oral zinc sulfate beginning in 1975. Furthermore, we report for the first time that analysis of zinc in hair over a 30-yr period allows for the identification of individuals who might be heterozygous carriers of this autosomal recessive disease and who, therefore, would be expected to have hair zinc levels intermediate between normal, healthy individuals and those with Acrodermatitis enteropathica. Zinc treatment of the two patients with Acrodermatitis enteropathica resulted in remission of the signs and symptoms of the disease within the first month of therapy. However, any short-term interruption (typically, 7-10 d) in oral zinc resulted in an almost immediate relapse, with the reappearance of the skin lesions. We also document the inverse relationship that exists between zinc and copper through analysis of these metals in the scalp hair from the two patients, thus providing a tool for ensuring adequate copper intake in patients taking relatively high doses of zinc over a long period.


Assuntos
Acrodermatite/genética , Triagem de Portadores Genéticos , Cabelo/química , Zinco/análise , Acrodermatite/tratamento farmacológico , Adolescente , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Zinco/uso terapêutico
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