969 resultados para Melanocytic Skin-cancer
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While knowledge about standardization of skin protection against ultraviolet radiation (UVR) has progressed over the past few decades, there is no uniform and generally accepted standardized measurement for UV eye protection. The literature provides solid evidence that UV can induce considerable damage to structures of the eye. As well as damaging the eyelids and periorbital skin, chronic UV exposure may also affect the conjunctiva and lens. Clinically, this damage can manifest as skin cancer and premature skin ageing as well as the development of pterygia and premature cortical cataracts. Modern eye protection, used daily, offers the opportunity to prevent these adverse sequelae of lifelong UV exposure. A standardized, reliable and comprehensive label for consumers and professionals is currently lacking. In this review we (i) summarize the existing literature about UV radiation-induced damage to the eye and surrounding skin; (ii) review the recent technological advances in UV protection by means of lenses; (iii) review the definition of the Eye-Sun Protection Factor (E-SPF®), which describes the intrinsic UV protection properties of lenses and lens coating materials based on their capacity to absorb or reflect UV radiation; and (iv) propose a strategy for establishing the biological relevance of the E-SPF. © 2013 John Wiley & Sons A/S.
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Melanoma is one of the most aggressive types of cancer. It originates from the transformation of melanocytes present in the epidermal/dermal junction of the human skin. It is commonly accepted that melanomagenesis is influenced by the interaction of environmental factors, genetic factors, as well as tumor-host interactions. DNA photoproducts induced by UV radiation are, in normal cells, repaired by the nucleotide excision repair (NER) pathway. The prominent role of NER in cancer resistance is well exemplified by patients with Xeroderma Pigmentosum (XP). This disease results from mutations in the components of the NER pathway, such as XPA and XPC proteins. In humans, NER pathway disruption leads to the development of skin cancers, including melanoma. Similar to humans afflicted with XP, Xpa and Xpc deficient mice show high sensibility to UV light, leading to skin cancer development, except melanoma. The Endothelin 3 (Edn3) signaling pathway is essential for proliferation, survival and migration of melanocyte precursor cells. Excessive production of Edn3 leads to the accumulation of large numbers of melanocytes in the mouse skin, where they are not normally found. In humans, Edn3 signaling pathway has also been implicated in melanoma progression and its metastatic potential. The goal of this study was the development of the first UV-induced melanoma mouse model dependent on the over-expression of Edn3 in the skin. The UV-induced melanoma mouse model reported here is distinguishable from all previous published models by two features: melanocytes are not transformed a priori and melanomagenesis arises only upon neonatal UV exposure. In this model, melanomagenesis depends on the presence of Edn3 in the skin. Disruption of the NER pathway due to the lack of Xpa or Xpc proteins was not essential for melanomagenesis; however, it enhanced melanoma penetrance and decreased melanoma latency after one single neonatal erythemal UV dose. Exposure to a second dose of UV at six weeks of age did not change time of appearance or penetrance of melanomas in this mouse model. Thus, a combination of neonatal UV exposure with excessive Edn3 in the tumor microenvironment is sufficient for melanomagenesis in mice; furthermore, NER deficiency exacerbates this process.^
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Melanoma is one of the most aggressive types of cancer. It originates from the transformation of melanocytes present in the epidermal/dermal junction of the human skin. It is commonly accepted that melanomagenesis is influenced by the interaction of environmental factors, genetic factors, as well as tumor-host interactions. DNA photoproducts induced by UV radiation are, in normal cells, repaired by the nucleotide excision repair (NER) pathway. The prominent role of NER in cancer resistance is well exemplified by patients with Xeroderma Pigmentosum (XP). This disease results from mutations in the components of the NER pathway, such as XPA and XPC proteins. In humans, NER pathway disruption leads to the development of skin cancers, including melanoma. Similar to humans afflicted with XP, Xpa and Xpc deficient mice show high sensibility to UV light, leading to skin cancer development, except melanoma. The Endothelin 3 (Edn3) signaling pathway is essential for proliferation, survival and migration of melanocyte precursor cells. Excessive production of Edn3 leads to the accumulation of large numbers of melanocytes in the mouse skin, where they are not normally found. In humans, Edn3 signaling pathway has also been implicated in melanoma progression and its metastatic potential. The goal of this study was the development of the first UV-induced melanoma mouse model dependent on the over-expression of Edn3 in the skin. The UV-induced melanoma mouse model reported here is distinguishable from all previous published models by two features: melanocytes are not transformed a priori and melanomagenesis arises only upon neonatal UV exposure. In this model, melanomagenesis depends on the presence of Edn3 in the skin. Disruption of the NER pathway due to the lack of Xpa or Xpc proteins was not essential for melanomagenesis; however, it enhanced melanoma penetrance and decreased melanoma latency after one single neonatal erythemal UV dose. Exposure to a second dose of UV at six weeks of age did not change time of appearance or penetrance of melanomas in this mouse model. Thus, a combination of neonatal UV exposure with excessive Edn3 in the tumor microenvironment is sufficient for melanomagenesis in mice; furthermore, NER deficiency exacerbates this process.
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This study intends to establish a relation between environmental degradation, particularly the devastation of the green canopy, and public health. Utilizing a mapping of the trees included in the researched area, each individual tree was analyzed according to its age, taxonomic listing, architecture, shape and size (determined by aesthetic/convenience reasons or deformed by pruning). Initially investigated were the covert reasons lying underneath the constant aggression against trees (which many times seem to contain elements of hatred and contempt) within the urban environment. In addition to that, the aspects concerning environmental modifications and the consequent impact on public health were also assessed. Two main problems promptly emerged as a result of the removal of trees: a) without a canopy to protect the areas, they became subject to winds directly blown from SW Africa and impregnated with aerosol partic les, which are common causes for respiratory disorders and, b) direct UV solar radiation, which causes some types of skin cancers and eye disorders. To reach such results, we studied the origins and formation of UV radiation induced cancers and searched for the UV radiation spectra of action, e.g., usual intensity and quantity reaching clear and shadowed spaces in a certain area and its consequences. In a second instance, we also searched for pertinent data resources in order to confirm the increase of skin cancer cases due to exposure to UV radiation and the relation between the destruction of the green canopy and the above mentioned problems. We believe that a few significant results have been achieved by this study, namely: the relation between a culture based on medieval beliefs and its consequences on the environment; how this culture exploits and deforms nature in pursuit of financial and psychological interests to a point of transforming the landscape into a copy of something devoid of any relation to latitude and altitude; and above all, the indifference concerning the alarming results carried by these modifications
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This study intends to establish a relation between environmental degradation, particularly the devastation of the green canopy, and public health. Utilizing a mapping of the trees included in the researched area, each individual tree was analyzed according to its age, taxonomic listing, architecture, shape and size (determined by aesthetic/convenience reasons or deformed by pruning). Initially investigated were the covert reasons lying underneath the constant aggression against trees (which many times seem to contain elements of hatred and contempt) within the urban environment. In addition to that, the aspects concerning environmental modifications and the consequent impact on public health were also assessed. Two main problems promptly emerged as a result of the removal of trees: a) without a canopy to protect the areas, they became subject to winds directly blown from SW Africa and impregnated with aerosol partic les, which are common causes for respiratory disorders and, b) direct UV solar radiation, which causes some types of skin cancers and eye disorders. To reach such results, we studied the origins and formation of UV radiation induced cancers and searched for the UV radiation spectra of action, e.g., usual intensity and quantity reaching clear and shadowed spaces in a certain area and its consequences. In a second instance, we also searched for pertinent data resources in order to confirm the increase of skin cancer cases due to exposure to UV radiation and the relation between the destruction of the green canopy and the above mentioned problems. We believe that a few significant results have been achieved by this study, namely: the relation between a culture based on medieval beliefs and its consequences on the environment; how this culture exploits and deforms nature in pursuit of financial and psychological interests to a point of transforming the landscape into a copy of something devoid of any relation to latitude and altitude; and above all, the indifference concerning the alarming results carried by these modifications
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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biologia Animal, 2016.
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Introducción: La incidencia del cáncer de piel melanoma y no melanoma es un problema de salud pública a nivel mundial. El incremento en la incidencia del cáncer de piel en los últimos años se debe a múltiples factores como: cambios en los estilos de vida, el envejecimiento de la población, cambios ambientales, el desconocimiento a la exposición a la radiación ultravioleta (RUV) durante la práctica de actividad física sin elementos de fotoprotección, siendo éste último reconocido como el principal factor de riesgo. Objetivo: Evaluar los efectos de una intervención educativa en los conocimientos y comportamientos relacionados con la fotoprotección durante la práctica de la actividad física en estudiantes de un colegio público de Bogotá D.C., Colombia. Métodos: Estudio de intervención, antes y después, no controlado en 281 estudiantes de los grados noveno, décimo y once de estratos 1-3 de un colegio público de Bogotá, con seguimiento a 1, 3 y 6 meses post-intervención. Se evaluaron los conocimientos y los hábitos de fotoprotección mediante un cuestionario Cancer Awareness Measure (CAM) y el modelo Transteórico de cambio comportamental de Prochaska y Di Clemente. El estudio se realizó durante el primer semestre de 2015 con 4 sesiones educativas de 60 minutos apoyadas con material audiovisual y pedagógico, acorde a la Guía para la Comunicación Educativa en el marco el control del cáncer publicada por el Instituto Nacional de Cancerología. Resultados: Del grupo de estudiantes que participaron del estudio, el 52,3% eran hombres, el promedio de edad fue de 15,46 ± 1,2 años. El tipo de piel predominante fue la trigueña con 65,8%. La intervención educativa produjo cambios significativos en los conocimientos de foto protección, finalizado el seguimiento al sexto mes. En cuanto a la prevención los estudiantes refirieron tener conocimiento de cómo examinar su piel en el momento basal (12,5% n=35), presentándose un aumento significativo de 62,6% (n=211) al sexto mes (p<0,05). Conclusión: El estudio demostró la efectividad de la intervención educativa, evidenciando cambios significativos en los conocimientos en fotoprotección y comportamientos preventivos del cáncer de piel durante la práctica de la actividad física en estudiantes de un colegio público de Bogotá D.C., Colombia.
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Cutaneous melanoma (CM) is a potentially lethal form of skin cancer and its most important histopathologic factor for staging is Breslow thickness (BT). Its correct determination is fundamental for pathologists. A deeper understanding of the molecular processes guiding CM pathogenesis could improve diagnosis, treatment and prognosis. MicroRNAs (miRNAs) play a key role in CM biology. The firs aim was to investigate miRNA expression in reference to BT assessment. We found that the combined miRNA expression of miR-21-5p and miR-146a-5p above or below 1.5 was significantly associated with overall survival and successfully identified all superficially spreading melanoma (SSM) patients with relapsing suggesting that the combined assessment of these miRNAs expression could aid in SSM staging. Secondly, we focus on multiple primary melanoma (MPM) patients, which develop multiple primary melanomas in their lifetime, and represent a model of high-risk CM occurrence. We explored the miRNome of single CM and MPM: CM and MPM present several dysregulated miRNAs, including key miRNAs involved in epithelial-mesenchymal transition. A different miRNA profile was observed between 1st and 2nd melanoma from the same patient. MiRNA target analysis revealed a more differentiated and less invasive status of MPMs compared to CMs. This characterization of the miRNA regulatory network of MPMs highlights molecular features differentiating this subtype from CM. Recently, NGS experiments revealed the existence of miRNA variants (isomiRs) with different length and sequence. We identified a shorter 3’isoform as tenfold over-represented compared to the canonical form of miR-125a-5p. Target analysis revealed that miRNA shortening could change the pattern of target gene regulation. Finally, we study miRNA and isomiR dysregulation in benign nevi (BN) and CM and in CM and melanoma metastasis. The reported non-random dysregulation of specific isomiRs contributes to the understanding of the complex melanoma pathogenesis and serves as the basis for further functional studies.
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MicroRNAs act as oncogene or tumor suppressor gene regulators and are actively released from tumor cells in the circulation. Specific microRNAs can be isolated and quantified in the blood, usually in serum or plasma fractions, where they are uncommonly stable. Cell-free microRNAs serve many, and possibly yet unexplored, functional roles and microRNA levels reflect underlying conditions and have been associated with skin cancer presence, stage and evolution. However, the clinical potential of circulating miRNAs in metastatic melanoma remains largely undefined. From May 2020 to September 2022, we conducted a spontaneous, monocentric, exploratory study on human tissues in vitro, which aimed to evaluate the prognostic and predictive role of circulating miRNAs in metastatic melanoma patients. At the Medical Oncology Unit of Policlinico Sant’Orsola-Malpighi of Bologna, peripheral venous blood samples from patients with metastatic melanoma treated with checkpoint inhibitors (CPI) were collected before the start of CPI (baseline, T0) and longitudinally, approximately every 3 months (T1, T2, etc). Circulating miRNA quantification was performed by droplet digital PCR (Biorad) using an EvaGreen and LNA primer-based assays. QuantaSoft Program (Biorad) calculated the absolute quantifications of each miRNA, indicated as copies/µL. After analysis of the literature, we chose to analyze miR-155-5p, miR-320a and miR-424-5p level. All miRNAs except miR-424-5p show a significantly higher level in plasma of patients who are alive after 1 year of follow-up. High/low levels of baseline miR-155-5p, miR-320a and miR-424-5p are significantly associated with overall survival and progression-free survival. Furthermore, a preliminary analysis on the group of patients who received first-line with anti-PD-1 (N=7), baseline miR-155-5p shows higher levels in responder vs. non responder patients (p 0.06). These data, though promising, are preliminary and need to be further investigated in a larger cohort of patients.
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INTRODUCTION Radiotherapy outcomes might be further improved by a greater understanding of the individual variations in normal tissue reactions that determine tolerance. Most published studies on radiation toxicity have been performed retrospectively. Our prospective study was launched in 1996 to measure the in vitro radiosensitivity of peripheral blood lymphocytes before treatment with radical radiotherapy in patients with breast cancer, and to assess the early and the late radiation skin side effects in the same group of patients. We prospectively recruited consecutive breast cancer patients receiving radiation therapy after breast surgery. To evaluate whether early and late side effects of radiotherapy can be predicted by the assay, a study was conducted of the association between the results of in vitro radiosensitivity tests and acute and late adverse radiation effects. METHODS Intrinsic molecular radiosensitivity was measured by using an initial radiation-induced DNA damage assay on lymphocytes obtained from breast cancer patients before radiotherapy. Acute reactions were assessed in 108 of these patients on the last treatment day. Late morbidity was assessed after 7 years of follow-up in some of these patients. The Radiation Therapy Oncology Group (RTOG) morbidity score system was used for both assessments. RESULTS Radiosensitivity values obtained using the in vitro test showed no relation with the acute or late adverse skin reactions observed. There was no evidence of a relation between acute and late normal tissue reactions assessed in the same patients. A positive relation was found between the treatment volume and both early and late side effects. CONCLUSION After radiation treatment, a number of cells containing major changes can have a long survival and disappear very slowly, becoming a chronic focus of immunological system stimulation. This stimulation can produce, in a stochastic manner, late radiation-related adverse effects of varying severity. Further research is warranted to identify the major determinants of normal tissue radiation response to make it possible to individualize treatments and improve the outcome of radiotherapy in cancer patients.
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One of the possible courses of cancer treatment is teletherapy, and one of the most important adverse side effects are skin reactions, an ailment more commonly called radiodermatitis. The main purpose of this study is to analyze knowledge of the evidence about topical products used in the prevention of radiodermatitis, to support care delivery to women with breast cancer during teletherapy. The research method used here is the comprehensive literature review. Four databases were used to select the bibliography. The sample consists of 15 articles. The data shows that, among the topical products analyzed here, Calendula, corticosteroids and Xclair have shown significant protective effects, underlining their actions. The lack of articles published in Brazil highlights the need for further research in this area, seeking better care quality through the use of products with scientifically proven efficiency.
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Survivin is a member of the inhibitor of apoptosis (IAP) protein family acting at the intersection between proliferation and cell survival. This protein exhibits low or undetectable expression in most adult tissues but is increased in the majority of cancers. Suggested to be one of the most cancer-specific proteins identified to date, survivin acts as a signalling node in tumour maintenance and, after first promising results, is now attracting increasing attention as a target in anti-cancer therapy. In the skin, survivin has been implicated in a number of pathological conditions such as psoriasis and tumours of melanocytic and epithelial origin. Its expression can correlate with tumour severity, metastasis and decreased patient survival and has been inversely correlated with the sensitivity to cytotoxic agents used in anti-cancer therapy. Survivin may also be of importance for normal epidermal homeostasis possibly supporting self-renewal of epidermal stem cells. In this review, the authors summarize and discuss current data of survivin in skin biology and provide a comprehensive compilation of survivin expression in skin pathologies with focus on future therapeutical use.