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Szasz A. Peto's "Paradox" and Six Degrees of Cancer Prevalence. Cells 2024; 13:197. [PMID: 38275822 PMCID: PMC10814230 DOI: 10.3390/cells13020197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/15/2024] [Accepted: 01/19/2024] [Indexed: 01/27/2024] Open
Abstract
Peto's paradox and the epidemiologic observation of the average six degrees of tumor prevalence are studied and hypothetically solved. A simple consideration, Petho's paradox challenges our intuitive understanding of cancer risk and prevalence. Our simple consideration is that the more a cell divides, the higher the chance of acquiring cancerous mutations, and so the larger or longer-lived organisms have more cells and undergo more cell divisions over their lifetime, expecting to have a higher risk of developing cancer. Paradoxically, it is not supported by the observations. The allometric scaling of species could answer the Peto paradox. Another paradoxical human epidemiology observation in six average mutations is necessary for cancer prevalence, despite the random expectations of the tumor causes. To solve this challenge, game theory could be applied. The inherited and random DNA mutations in the replication process nonlinearly drive cancer development. The statistical variance concept does not reasonably describe tumor development. Instead, the Darwinian natural selection principle is applied. The mutations in the healthy organism's cellular population can serve the species' evolutionary adaptation by the selective pressure of the circumstances. Still, some cells collect multiple uncorrected mutations, adapt to the extreme stress in the stromal environment, and develop subclinical phases of cancer in the individual. This process needs extensive subsequent DNA replications to heritage and collect additional mutations, which are only marginal alone. Still, together, they are preparing for the first stage of the precancerous condition. In the second stage, when one of the caretaker genes is accidentally mutated, the caused genetic instability prepares the cell to fight for its survival and avoid apoptosis. This can be described as a competitive game. In the third stage, the precancerous cell develops uncontrolled proliferation with the damaged gatekeeper gene and forces the new game strategy with binary cooperation with stromal cells for alimentation. In the fourth stage, the starving conditions cause a game change again, starting a cooperative game, where the malignant cells cooperate and force the cooperation of the stromal host, too. In the fifth stage, the resetting of homeostasis finishes the subclinical stage, and in the fifth stage, the clinical phase starts. The prevention of the development of mutated cells is more complex than averting exposure to mutagens from the environment throughout the organism's lifetime. Mutagenic exposure can increase the otherwise random imperfect DNA reproduction, increasing the likelihood of cancer development, but mutations exist. Toxic exposure is more challenging; it may select the tolerant cells on this particular toxic stress, so these mutations have more facility to avoid apoptosis in otherwise collected random mutational states.
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Affiliation(s)
- Andras Szasz
- Department of Biotechnics, Hungarian University of Agriculture and Life Sciences, 2100 Gödöllő, Hungary
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Proietto M, Crippa M, Damiani C, Pasquale V, Sacco E, Vanoni M, Gilardi M. Tumor heterogeneity: preclinical models, emerging technologies, and future applications. Front Oncol 2023; 13:1164535. [PMID: 37188201 PMCID: PMC10175698 DOI: 10.3389/fonc.2023.1164535] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 04/11/2023] [Indexed: 05/17/2023] Open
Abstract
Heterogeneity describes the differences among cancer cells within and between tumors. It refers to cancer cells describing variations in morphology, transcriptional profiles, metabolism, and metastatic potential. More recently, the field has included the characterization of the tumor immune microenvironment and the depiction of the dynamics underlying the cellular interactions promoting the tumor ecosystem evolution. Heterogeneity has been found in most tumors representing one of the most challenging behaviors in cancer ecosystems. As one of the critical factors impairing the long-term efficacy of solid tumor therapy, heterogeneity leads to tumor resistance, more aggressive metastasizing, and recurrence. We review the role of the main models and the emerging single-cell and spatial genomic technologies in our understanding of tumor heterogeneity, its contribution to lethal cancer outcomes, and the physiological challenges to consider in designing cancer therapies. We highlight how tumor cells dynamically evolve because of the interactions within the tumor immune microenvironment and how to leverage this to unleash immune recognition through immunotherapy. A multidisciplinary approach grounded in novel bioinformatic and computational tools will allow reaching the integrated, multilayered knowledge of tumor heterogeneity required to implement personalized, more efficient therapies urgently required for cancer patients.
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Affiliation(s)
- Marco Proietto
- Next Generation Sequencing Core, The Salk Institute for Biological Studies, La Jolla, CA, United States
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, United States
- NOMIS Center for Immunobiology and Microbial Pathogenesis, The Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Martina Crippa
- Vita-Salute San Raffaele University, Milan, Italy
- Experimental Imaging Center, Istituti di Ricovero e Cura a Carattere Scientifico (IRCCS) Ospedale San Raffaele, Milan, Italy
| | - Chiara Damiani
- Infrastructure Systems Biology Europe /Centre of Systems Biology (ISBE/SYSBIO) Centre of Systems Biology, Milan, Italy
- Department of Biotechnology and Biosciences, School of Sciences, University of Milano-Bicocca, Milan, Italy
| | - Valentina Pasquale
- Infrastructure Systems Biology Europe /Centre of Systems Biology (ISBE/SYSBIO) Centre of Systems Biology, Milan, Italy
- Department of Biotechnology and Biosciences, School of Sciences, University of Milano-Bicocca, Milan, Italy
| | - Elena Sacco
- Infrastructure Systems Biology Europe /Centre of Systems Biology (ISBE/SYSBIO) Centre of Systems Biology, Milan, Italy
- Department of Biotechnology and Biosciences, School of Sciences, University of Milano-Bicocca, Milan, Italy
| | - Marco Vanoni
- Infrastructure Systems Biology Europe /Centre of Systems Biology (ISBE/SYSBIO) Centre of Systems Biology, Milan, Italy
- Department of Biotechnology and Biosciences, School of Sciences, University of Milano-Bicocca, Milan, Italy
- *Correspondence: Marco Vanoni, ; Mara Gilardi,
| | - Mara Gilardi
- NOMIS Center for Immunobiology and Microbial Pathogenesis, The Salk Institute for Biological Studies, La Jolla, CA, United States
- Salk Cancer Center, The Salk Institute for Biological Studies, La Jolla, CA, United States
- *Correspondence: Marco Vanoni, ; Mara Gilardi,
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Xu N, Chen Y, Guo D, Deng Y, Guo W, Liu X, Wang Y, Lu H, Liu A, Zhu J, Li F. Rhein promotes the proliferation of keratinocytes by targeting oestrogen receptors for skin ulcer treatment. BMC Complement Med Ther 2022; 22:209. [PMID: 35932049 PMCID: PMC9354312 DOI: 10.1186/s12906-022-03691-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 07/28/2022] [Indexed: 11/10/2022] Open
Abstract
Background The Sheng-ji Hua-yu (SJHY) formula is a quite effective Traditional Chinese Medicines (TCM) in the treatment of delayed diabetic wounds. Previous research has shown that the SJHY formula has significant anti-inflammatory and wound-healing effects, but the precise mechanism remains unknown. The purpose of this study was to evaluate the effects of rhein, a compound extracted from SJHY formula, in keratinocytes and to investigate the underlying mechanisms. Methods Microscale thermophoresis (MST) technology was used to confirm that rhein binds directly to oestrogen receptors (ERs). Rhein was then used to treat keratinocytes in vitro. Cell cycle and proliferation analysis, Real-time polymerase chain reaction (RT-PCR) and Western-blot were conducted. Results Rhein increased the proportion of cells in the S phase of the cell cycle and promoted keratinocyte proliferation. ICI 182,780, an ER inhibitor, was also used to treat keratinocytes. The expression of c-myc mRNA and protein induced by rhein was antagonized by ICI 182,780, indicating that this induction is ER dependent. Intervention with ICI 182,780 had no effect on the upregulation of FosB and JunD, indicating that activator protein 1 (AP-1) members (FosB and JunD) are involved in rhein-induced c-myc mRNA and protein expression but does not require the ER. Conclusion The present study found that rhein stimulates keratinocyte proliferation by activating the oestrogen signalling pathway via the oestrogen receptor, which induces the expression of c-myc in collaboration with FosB and JunD, thereby accelerating the process of re-epithelialization. Supplementary Information The online version contains supplementary material available at 10.1186/s12906-022-03691-1.
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Liaw CC, Liao TY, Tsui KH, Juan YH. Survival Benefit for Patients With Metastatic Urothelial Carcinoma Receiving Continuous Maintenance Chemotherapy. In Vivo 2019; 33:1249-1262. [PMID: 31280216 DOI: 10.21873/invivo.11597] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 05/28/2019] [Accepted: 06/03/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND/AIM Urothelial carcinoma is a chemo-sensitive cancer. We investigated the contributory factors to survival benefit of metastatic urothelial carcinoma (MUC) patients receiving continuous maintenance chemotherapy. PATIENTS AND METHODS Inclusion criteria were: i) pathology-confirmed urothelial carcinoma, ii) metastatic lesions identified mainly on pre-therapy computed tomography (CT) scans, and iii) inpatient-administered chemotherapy of at least three cycles. Chemotherapy regimens included 5-fluorouracil, leucovorin, cisplatin, and gemcitabine. RESULTS A total of 139 cases were enrolled in this study. The overall objective response rate was 60% and the median survival time was 17 months. Eight-two (59%) patients had inflammation-related symptoms following the course of chemotherapy. Fifty-five (41%) patients survived more than two years. All patients exhibited various fibrosis formations. No patient experienced unfavorable metastatic conditions. Inflammation-related symptoms remained in 28 (51%) patients. We found that surgery, invasive procedures, and infection likely led to a rapid tumor progression. CONCLUSION Continuous maintenance chemotherapy targeting chemo-sensitive tumors, administered at metronomic intervals and focus on tumor microenvironment, can increase MUC survival benefits.
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Affiliation(s)
- Chuang-Chi Liaw
- Division of Hemato-Oncology, Department of Internal Medicine Chang-Gung Memorial Hospital and Chang-Gung University College of Medicine, Taoyuan, Taiwan, R.O.C.
| | - Tzu-Yao Liao
- Division of Hemato-Oncology, Department of Internal Medicine Chang-Gung Memorial Hospital and Chang-Gung University College of Medicine, Taoyuan, Taiwan, R.O.C
| | - Ke-Hung Tsui
- Department of Urology, Chang-Gung Memorial Hospital and Chang-Gung University College of Medicine, Taoyuan, Taiwan, R.O.C
| | - Yu-Hsiang Juan
- Department of Medical Imaging and Intervention, Chang-Gung Memorial Hospital and Chang-Gung University College of Medicine, Taoyuan, Taiwan, R.O.C
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An allometric approach of tumor-angiogenesis. Med Hypotheses 2018; 116:74-78. [DOI: 10.1016/j.mehy.2018.03.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 03/13/2018] [Accepted: 03/25/2018] [Indexed: 01/27/2023]
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Langevin SM, Kratzke RA, Kelsey KT. Epigenetics of lung cancer. Transl Res 2015; 165:74-90. [PMID: 24686037 PMCID: PMC4162853 DOI: 10.1016/j.trsl.2014.03.001] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 02/25/2014] [Accepted: 03/06/2014] [Indexed: 12/20/2022]
Abstract
Lung cancer is the leading cause of cancer-related mortality in the United States. Epigenetic alterations, including DNA methylation, histone modifications, and noncoding RNA expression, have been reported widely in the literature to play a major role in the genesis of lung cancer. The goal of this review is to summarize the common epigenetic changes associated with lung cancer to give some clarity to its etiology, and to provide an overview of the potential translational applications of these changes, including applications for early detection, diagnosis, prognostication, and therapeutics.
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Affiliation(s)
- Scott M Langevin
- Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Robert A Kratzke
- Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota Medical School, Minneapolis, Minn
| | - Karl T Kelsey
- Department of Epidemiology, Brown University, Providence, RI; Department of Pathology and Laboratory Medicine, Brown University, Providence, RI.
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Park SS, Izadjoo MJ. Wound infections and healing: are they contributing factors for carcinogenesis? J Wound Care 2014; 23:314, 316-9, 321-2 passim. [PMID: 24920202 DOI: 10.12968/jowc.2014.23.6.314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The link between inflammation and tumourisation has long been considered as a key event in clinical cancer development. Inflammation and inflammatory diseases can be caused by many factors including infectious agents, altered genetics and various degrees of injuries from simple cuts to traumatic wounds, such as those suffered in battlefield. Improved management of all wound types is critical in protecting affected individuals against the development of tumourisation cues, which may potentially lead to cancer development. There have been numerous studies on the mechanism of inflammation-induced tumourisation. Thus, in this mini review, we summarised evidence demonstrating the potential link between infectious agents and their moonlight proteins, wounding, trauma, overactive repair mechanisms, and carcinogenesis.
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Affiliation(s)
- S S Park
- PhD, Research Scientist, Diagnostics and Translational Research Center, The Henry M. Jackson Foundation for the Advancement of Military Medicine, Gaithersburg, US
| | - M J Izadjoo
- PhD, Senior Distinguished Scientist, Diagnostics and Translational Research Center, The Henry M. Jackson Foundation for the Advancement of Military Medicine, Gaithersburg, US
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Sun K, Deng W, Zhang S, Cai N, Jiao S, Song J, Wei L. Paradoxical roles of autophagy in different stages of tumorigenesis: protector for normal or cancer cells. Cell Biosci 2013; 3:35. [PMID: 24016776 PMCID: PMC3849558 DOI: 10.1186/2045-3701-3-35] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 08/01/2013] [Indexed: 12/20/2022] Open
Abstract
Autophagy serves as a dynamic degradation and recycling system that provides biological materials and energy in response to stress. The role of autophagy in tumor development is complex. Various studies suggest that autophagy mainly contributes to tumor suppression during the early stage of tumorigenesis and tumor promotion during the late stage of tumorigenesis. During the tumorization of normal cells, autophagy protects genomic stability by retarding stem cells-involved damage/repair cycle, and inhibits the formation of chronic inflammatory microenvironment, thus protecting normal cell homeostasis and preventing tumor generation. On the other hand, autophagy also protects tumor cells survival during malignant progression by supporting cellular metabolic demands, decreasing metabolic damage and supporting anoikis resistance and dormancy. Taken together, autophagy appears to play a role as a protector for either normal or tumor cells during the early or late stage of tumorigenesis, respectively. The process of tumorigenesis perhaps needs to undergo twice autophagy-associated screening. The normal cells that have lower autophagy capacity are prone to tumorization, and the incipient tumor cells that have higher autophagy capacity possibly are easier to survival in the hash microenvironment and accumulate more mutations to promote malignant progression.
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Affiliation(s)
- Kai Sun
- Medical Sciences Research Center, Renji hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China.
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Sun K, Guo XL, Zhao QD, Jing YY, Kou XR, Xie XQ, Zhou Y, Cai N, Gao L, Zhao X, Zhang SS, Song JR, Li D, Deng WJ, Li R, Wu MC, Wei LX. Paradoxical role of autophagy in the dysplastic and tumor-forming stages of hepatocarcinoma development in rats. Cell Death Dis 2013; 4:e501. [PMID: 23429287 PMCID: PMC3734842 DOI: 10.1038/cddis.2013.35] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Many reports have shown that autophagy has a role as both a promoter and inhibitor in tumor development. However, the mechanism of this paradox is unknown. Tumor development is a multistep process. Therefore, we investigated whether the role of autophagy in hepatocarcinoma formation depended on the stage of tumor development. Based on our results, autophagy inhibition by chloroquine had a tumor-promotive effect in the rat model with N-diethylnitrosamine-induced hepatocarcinogenesis in its dysplastic stage (Ds) and a tumor-suppressive effect in its tumor-forming stage (Ts). In the Ds, autophagy inhibition enhanced cell proliferation, DNA damage and inflammatory cytokines expression in liver. These changes were dependent on the upregulation of reactive oxygen species (ROS) that was resulted from autophagy inhibition, and ultimately accelerated the process of hepatocarcinogenesis. However, in the Ts, autophagy inhibition restrained tumor formation by decreasing tumor cell survival and proliferation. In this stage, autophagy inhibition led to excessive ROS accumulation in the tumor, which promoted cell apoptosis, and prominently suppressed tumor cell metabolism. Taken together, our data suggested that autophagy suppressed hepatocarcinogenesis in the Ds by protecting normal cell stability and promoted hepatocarcinogenesis in the Ts by supporting tumor cells growth. Autophagy always had a role as a protector throughout the process of hepatocarcinoma development.
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Affiliation(s)
- K Sun
- Medical Sciences Research Center, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
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WANG NA, LI MIN, ZANG WENQIAO, MA YUNYUN, WANG YUANYUAN, ZHAO GUOQIANG. Effects of cyclin E gene silencing on the proliferation of esophageal cancer cell lines, EC9706, Eca109 and KYSE30. Mol Med Rep 2013; 7:799-804. [DOI: 10.3892/mmr.2013.1280] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 01/10/2013] [Indexed: 11/05/2022] Open
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The cancer epigenome: its origins, contributions to tumorigenesis, and translational implications. Ann Am Thorac Soc 2012; 9:64-5. [PMID: 22550245 DOI: 10.1513/pats.201201-001ms] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Epigenetic abnormalities in lung and other cancers continue to be defined at a rapid pace. We are coming to appreciate that cancers have an "epigenetic landscape" wherein genes vulnerable to abnormalities, such as promoter DNA hypermethylation and associated gene silencing, tend to reside in defined nuclear positions and chromosome domains and relationships to chromatin regulation, which facilitates states of stem cell renewal. These same genes and domains are also vulnerable to epigenetic abnormalities induced by factors to which cells are exposed during cancer risk states, such as chronic inflammation. We can use all of this basic information for translational purposes in terms of deriving biomarkers for cancer risk states and detection and therapeutic strategies.
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Induction the cornification of squamous cancerous cells to eliminate tumor cells by promotion cell differentiation and stratum. Med Hypotheses 2011; 77:763-4. [DOI: 10.1016/j.mehy.2011.07.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Accepted: 07/18/2011] [Indexed: 01/05/2023]
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Abstract
The past decade has highlighted the central role of epigenetic processes in cancer causation, progression and treatment. Next-generation sequencing is providing a window for visualizing the human epigenome and how it is altered in cancer. This view provides many surprises, including linking epigenetic abnormalities to mutations in genes that control DNA methylation, the packaging and the function of DNA in chromatin, and metabolism. Epigenetic alterations are leading candidates for the development of specific markers for cancer detection, diagnosis and prognosis. The enzymatic processes that control the epigenome present new opportunities for deriving therapeutic strategies designed to reverse transcriptional abnormalities that are inherent to the cancer epigenome.
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Affiliation(s)
- Stephen B. Baylin
- The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, Maryland 21231, USA
| | - Peter A. Jones
- The USC Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California 90089, USA
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Johnstone SE, Baylin SB. Stress and the epigenetic landscape: a link to the pathobiology of human diseases? Nat Rev Genet 2010; 11:806-12. [PMID: 20921961 DOI: 10.1038/nrg2881] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Accumulating evidence points to a major role for chronic stress of cell renewal systems in the pathogenesis of important human diseases, including cancer, atherosclerosis and diabetes. Here we discuss emerging evidence that epigenetic abnormalities may make substantial contributions to these stress-induced pathologies. Although the mechanisms remain to be fully elucidated, we suggest that chronic stress can elicit heritable changes in the chromatin landscape that 'lock' cells in abnormal states, which then lead to disease. We emphasize the need to investigate epigenetic states in disease and links to stress and to consider how the knowledge gained through these studies may foster new means of disease prevention and management.
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Affiliation(s)
- Sarah E Johnstone
- The Sidney Kimmel Cancer Research Center at Johns Hopkins, Bunting Blaustein Cancer Research Building, 1650 Orleans Street, Suite 544, Baltimore, Maryland 21231-1000, USA
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Ao P, Galas D, Hood L, Zhu X. Cancer as robust intrinsic state of endogenous molecular-cellular network shaped by evolution. Med Hypotheses 2007; 70:678-84. [PMID: 17766049 PMCID: PMC3166219 DOI: 10.1016/j.mehy.2007.03.043] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2007] [Accepted: 03/28/2007] [Indexed: 10/22/2022]
Abstract
An endogenous molecular--cellular network for both normal and abnormal functions is assumed to exist. This endogenous network forms a nonlinear stochastic dynamical system, with many stable attractors in its functional landscape. Normal or abnormal robust states can be decided by this network in a manner similar to the neural network. In this context cancer is hypothesized as one of its robust intrinsic states. This hypothesis implies that a nonlinear stochastic mathematical cancer model is constructible based on available experimental data and its quantitative prediction is directly testable. Within such model the genesis and progression of cancer may be viewed as stochastic transitions between different attractors. Thus it further suggests that progressions are not arbitrary. Other important issues on cancer, such as genetic vs epigenetics, double-edge effect, dormancy, are discussed in the light of present hypothesis. A different set of strategies for cancer prevention, cure, and care, is therefore suggested.
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Affiliation(s)
- Ping Ao
- Department of Mechanical Engineering and Department of Physics, University of Washington, Seattle, WA 98195, USA.
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Rodríguez-Molinero A, López-Diéguez M, Banegas JR. Tissue homeostasis and cancer. Med Hypotheses 2007; 68:1333-41. [PMID: 17157444 DOI: 10.1016/j.mehy.2006.10.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2006] [Accepted: 10/10/2006] [Indexed: 01/02/2023]
Abstract
Epithelial cells are known to release an important amount of cytokines capable to modulate immune system functions. On the other hand, immune system cells can release cytokines, which play an important role in the control of the growth of epithelial cells. In this paper, we stand the hypothesis that a mutual (reciprocal) growth regulation exists between epithelial cells and immune system. We propose a model describing plausible cytokine circuits that may regulate (inhibit) both epithelial growth and epithelial inflammation. In addition, we describe how dysfunction of these circuits could lead to tumoral growth, excessive inflammation or both. A failure in the regulation of epithelial growth by the immune system could give rise to a neoplasm, and a failure in the regulation of the immune system by the epithelium could give rise to inflammatory or autoimmune diseases. This model may satisfactorily explain the link between inflammation and cancer.
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Affiliation(s)
- Alejandro Rodríguez-Molinero
- Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid, Arzobispo Morcillo 2, 28029, Madrid, Spain.
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Wu XZ. Cancer and chronic tissue injury: Abnormal repair tissue or functional repair tissue? Med Hypotheses 2006; 67:676-7. [PMID: 16678354 DOI: 10.1016/j.mehy.2006.03.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2006] [Accepted: 03/21/2006] [Indexed: 10/24/2022]
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Martinez-Borges AR. Turbulent urinary flow in the urethra could be a causal factor for benign prostatic hyperplasia. Med Hypotheses 2006; 67:871-5. [DOI: 10.1016/j.mehy.2006.02.055] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2006] [Accepted: 02/27/2006] [Indexed: 11/28/2022]
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