DNA Of Skin Cells Research Articles

Skin Cancer Classification using Deep Learning

According to world health organization skin cancer is the one of the most common cancer types in the world. The abnormal growth of skin cells most often develops on the skin when exposed to the sun and occurs when there is a mutation in the DNA of skin cells, it begins at the top of the skin. More than five million people are affected by skin cancer each year. The proposed method aim at analyzing and detecting the significant class of skin cancer variant such as Melanoma, Basal cell Carcinoma, Nevus. Melanoma is the most dangerous form of skin cancer when compared to the other types. In this paper we have developed a webapp that could differentiate skin cancer. The data set has been taken from ISIC and the model is trained using Gcollab. The proposed work has used convolution neural network (CNN) as algorithm for deep learning as it has higher accuracy and flask is used to develop the web app and the class of cancer is classified based on historical data of dermoscopic images.

TiO2-Alginate-Chitosan-Based Composites for Skin Tissue Engineering Applications.

The UV-B component of sunlight damages the DNA in skin cells, which can lead to skin cancer and premature aging. Therefore, it is necessary to use creams that also contain UV-active substances. Many sunscreens contain titanium dioxide due to its capacity to absorb UV-B wavelengths. In the present study, titan dioxide was introduced in alginate and chitosan-alginate hydrogel composites that are often involved as scaffold compositions in tissue engineering applications. Alginate and chitosan were chosen due to their important role in skin regeneration and skin protection. The composites were cross-linked with calcium ions and investigated using FT-IR, Raman, and UV-Vis spectroscopy. The stability of the obtained samples under solar irradiation for skin protection and regeneration was analyzed. Then, the hydrogel composites were assayed in vitro by immersing them in simulated body fluid and exposing them to solar simulator radiation for 10 min. The samples were found to be stable under solar light, and a thin apatite layer covered the surface of the sample with the two biopolymers and titanium dioxide. The in vitro cell viability assay suggested that the anatase phase in alginate and chitosan-alginate hydrogel composites have a positive impact.

Antioxidants in Photoaging: From Molecular Insights to Clinical Applications.

Photoaging (PA) is considered a silent disease affecting millions of people globally and is defined as skin damage due to prolonged exposure to ultraviolet radiation (UVR) from the sun. Physiologically, the skin is in a state of renewal and synthesis of components of the extracellular matrix (ECM). However, exposure to UVR affects the production of the ECM, and the functioning and response of skin cells to UVR begins to change, thus expressing clinical and phenotypic characteristics of PA. The primary mechanisms involved in PA are direct damage to the DNA of skin cells, increases in oxidative stress, the activation of cell signaling pathways responsible for the loss of skin integrity, and cytotoxicity. The medical and scientific community has been researching new therapeutic tools that counteract PA, considering that the damage caused by UVR exceeds the antioxidant defense mechanisms of the skin. Thus, in recent years, certain nutraceuticals and phytochemicals have been found to exhibit potential antioxidant and photoprotective effects. Therefore, the main objective of this review is to elucidate the molecular bases of PA and the latest pharmaceutical industry findings on antioxidant treatment against the progression of PA.

Ectoine Globally Hypomethylates DNA in Skin Cells and Suppresses Cancer Proliferation.

Epigenetic modifications, mainly aberrant DNA methylation, have been shown to silence the expression of genes involved in epigenetic diseases, including cancer suppression genes. Almost all conventional cancer therapeutic agents, such as the DNA hypomethylation drug 5-aza-2-deoxycytidine, have insurmountable side effects. To investigate the role of the well-known DNA protectant (ectoine) in skin cell DNA methylation and cancer cell proliferation, comprehensive methylome sequence analysis, 5-methyl cytosine (5mC) analysis, proliferation and tumorigenicity assays, and DNA epigenetic modifications-related gene analysis were performed. The results showed that extended ectoine treatment globally hypomethylated DNA in skin cells, especially in the CpG island (CGIs) element, and 5mC percentage was significantly reduced. Moreover, ectoine mildly inhibited skin cell proliferation and did not induce tumorigenicity in HaCaT cells injected into athymic nude mice. HaCaT cells treated with ectoine for 24 weeks modulated the mRNA expression levels of Dnmt1, Dnmt3a, Dnmt3b, Dnmt3l, Hdac1, Hdac2, Kdm3a, Mettl3, Mettl14, Snrpn, and Mest. Overall, ectoine mildly demethylates DNA in skin cells, modulates the expression of epigenetic modification-related genes, and reduces cell proliferation. This evidence suggests that ectoine is a potential anti-aging agent that prevents DNA hypermethylation and subsequently activates cancer-suppressing genes.

Melanoma Skin Cancer and Nevus Mole Classification using Intensity Value Estimation with Convolutional Neural Network

Melanoma skin cancer is one of the most dangerous and life-threatening cancer. Exposure to ultraviolet rays may damage the skin cell's DNA, which causes melanoma skin cancer. However, it is difficult to detect and classify melanoma and nevus mole at the immature stages. In this work, an automatic deep learning system is developed based on the intensity value estimation with a convolutional neural network model (CNN) to detect and classify melanoma and nevus mole more accurately. Since intensity levels are the most distinctive features for object or region of interest identification, the high-intensity pixel values are selected from the extracted lesion images. Incorporating those high-intensity features into the CNN improves the overall performance than the state-of-the-art methods for detecting melanoma skin cancer. To evaluate the system, we used 5-fold cross-validation. Experimental results show that a superior percentage of accuracy (92.58%), Sensitivity (93.76%), Specificity (91.56%), and Precision (90.68%) are achieved.

High-resolution melt analysis for the detection of skin/sweat via DNA methylation.

The determination of tissue type is important when reconstructing a crime scene as skin cells may indicate innocent contact, whereas other types of cells, such as blood and semen, may indicate foul play. Up to now, there has been no specific DNA methylation-based marker to distinguish skin cell DNA from other body fluids. The goal of this study is to develop a DNA methylation-based assay to detect and identify skin cells collected at forensic crime scenes for use in DNA typing. For this reason, we have utilized a DNA methylation chip array-based genome-wide association study to identify skin-specific DNA methylation markers. DNA obtained from skin along with other body fluids, such as semen, saliva, blood, and vaginal epithelia, were tested using five genes that were identified as sites for potential new epigenetic skin markers. Samples were collected, bisulfite converted, and subjected to real-time polymerase chain reaction (PCR) with high-resolution melt analysis. In our studies, when using WDR11, PON2, and NHSL1 assays with bisulfite-modified PCR, skin/sweat amplicons melted at lower temperatures compared to blood, saliva, semen, and vaginal epithelia. One-way analysis of variance demonstrates that these three skin/sweat markers are significantly different when compared with other body fluids (p<0.05). These results demonstrate that high-resolution melt analysis is a promising technology to detect and identify skin/sweat DNA from other body fluids.

Classification of Skin Cancer Images Using Convolutional Neural Networks

Skin cancer is the most common human malignancy according to American Cancer Society. It is primarily diagnosed visually, starting with an initial clinical screening and followed potentially by dermoscopic (related to skin) analysis, a biopsy and histopathological examination. Skin cancer occurs when errors (mutations) occur in the DNA of skin cells. The mutations cause cells to grow out of control and form a mass of cancer cells. The aim of this study was to try to classify images of skin lesions with the help of Convolutional Neural Networks. Deep neural networks show humongous potential for image classification while taking into account the large variability exhibited by the environment. Here, we trained images on the basis of pixel values and classified them on the basis of disease labels. The dataset was acquired from an Open Source Kaggle Repository (Kaggle Dataset) which itself was acquired from ISIC (International Skin Imaging Collaboration) archive. The training was performed on multiple models accompanied with Transfer Learning. The highest model accuracy achieved was over 86.65%. The dataset used is publicly available to ensure credibility and reproducibility of the aforementioned result.

Reactions of 3\u2032,5\u2032-di-O-acetyl-2\u2032-deoxyguansoine and 3\u2032,5\u2032-di-O-acetyl-2\u2032-deoxyadenosine to UV light in the presence of uric acid

IntroductionRecently, it was revealed that uric acid is a photosensitizer of reactions of nucleosides on irradiation with UV light at wavelengths longer than 300 nm, and two products generated from 2′-deoxycytidine were identified. In the present study, UV reactions of acetylated derivatives of 2′-deoxyguansoine and 2′-deoxyadenosine were conducted and their products were identified.FindingsEach reaction of 3′,5′-di-O-acetyl-2′-deoxyguansoine or 3′,5′-di-O-acetyl-2′-deoxyadenosine with UV light at wavelengths longer than 300 nm in the presence of uric acid generated several products. The products were separated by HPLC and identified by comparing UV and MS spectra of the products with previously reported values. The major products were spiroiminodihydantoin, imidazolone, and dehydro-iminoallantoin nucleosides for 3′,5′-di-O-acetyl-2′-deoxyguansoine, and an adenine base and a formamidopyrimidine nucleoside for 3′,5′-di-O-acetyl-2′-deoxyadenosine.ConclusionsIf these damages caused by uric acid with sunlight occur in DNA of skin cells, mutations may arise. We should pay attention to the genotoxicity of uric acid in terms of DNA damage to dGuo and dAdo sites mediated by sunlight.

Classification of Skin Cancer Images Using Convolutional Neural Networks

Skin cancer is the most common human malignancy(American Cancer Society) which is primarily diagnosed visually, starting with an initial clinical screening and followed potentially by dermoscopic(related to skin) analysis, a biopsy and histopathological examination. Skin cancer occurs when errors (mutations) occur in the DNA of skin cells. The mutations cause the cells to grow out of control and form a mass of cancer cells. The aim of this study was to try to classify images of skin lesions with the help of convolutional neural networks. The deep neural networks show humongous potential for image classification while taking into account the large variability exhibited by the environment. Here we trained images based on the pixel values and classified them on the basis of disease labels. The dataset was acquired from an Open Source Kaggle Repository(Kaggle Dataset)which itself was acquired from ISIC(International Skin Imaging Collaboration) Archive. The training was performed on multiple models accompanied with Transfer Learning. The highest model accuracy achieved was over 86.65%. The dataset used is publicly available to ensure credibility and reproducibility of the aforementioned result.

Astaxanthin Protects Ultraviolet B-Induced Oxidative Stress and Apoptosis in Human Keratinocytes via Intrinsic Apoptotic Pathway.

BackgroundUltraviolet radiation causes skin damage due to increased production of reactive oxygen species (ROS) and inflammatory intermediates and direct attack of DNA of skin cells. Astaxanthin is a reddish pigment that belongs to a group of chemicals called carotenoids and has protective effects as an antioxidant.ObjectiveTo determine the beneficial effects of astaxanthin on damaged human skin after exposure to ultraviolet radiation.MethodsNormal human epidermal keratinocytes (NHEKs) were pre-treated with astaxanthin for 24 hours and exposed to ultraviolet B (UVB) irradiation. After 24 hours, the Cell Counting Kit-8 (CCK-8) assay measured cell viability, ROS assay and flow cytometry analysis assessed apoptosis, and western blotting was performed to determine expression of apoptosis-related proteins.ResultsAstaxanthin significantly inhibited UVB-induced NHEKs cytotoxicity. Pretreatment of NHEKs with astaxanthin reduced UVB-induced ROS production. Astaxanthin caused significant inhibition of UVB-induced apoptosis, as evidenced by flow cytometry analysis and western blotting.ConclusionThese results suggest that astaxanthine has a beneficial effect of reducing damage caused by UVB by effectively inhibiting cell death and reducing ROS production in keratinocytes.

Oxidative stress in the skin: Impact and related protection.

Skin, our first interface to the external environment, is subjected to oxidative stress caused by a variety of factors such as solar ultraviolet, infrared and visible light, environmental pollution, including ozone and particulate matters, and psychological stress. Excessive reactive species, including reactive oxygen species and reactive nitrogen species, exacerbate skin pigmentation and aging, which further lead to skin tone unevenness, pigmentary disorder, skin roughness and wrinkles. Besides these, skin microbiota are also a very important factor ensuring the proper functions of skin. While environmental factors such as UV and pollutants impact skin microbiota compositions, skin dysbiosis results in various skin conditions. In this review, we summarize the generation of oxidative stress from exogenous and endogenous sources. We further introduce current knowledge on the possible roles of oxidative stress in skin pigmentation and aging, specifically with emphasis on oxidative stress and skin pigmentation. Meanwhile, we summarize the science and rationale of using three well-known antioxidants, namely vitamin C, resveratrol and ferulic acid, in the treatment of hyperpigmentation. Finally, we discuss the strategy for preventing oxidative stress-induced skin pigmentation and aging.

Sunscreens Containing Cyclodextrin Inclusion Complexes for Enhanced Efficiency: A Strategy for Skin Cancer Prevention.

Unprotected exposure of skin to solar ultraviolet radiation (UVR) may damage the DNA of skin cells and can lead to skin cancer. Sunscreens are topical formulations used to protect skin against UVR. The active ingredients of sunscreens are UV filters that absorb, scatter, and/or reflect UVR. Preventing the formation of free radicals and repairing DNA damages, natural antioxidants are also added to sunscreens as a second fold of protection against UVR. Antioxidants can help stabilise these formulations during the manufacturing process and upon application on skin. However, UV filters and antioxidants are both susceptible to degradation upon exposure to sunlight and oxygen. Additionally, due to their poor water solubility, natural antioxidants are challenging to formulate and exhibit limited penetration and bioavailability in the site of action (i.e., deeper skin layers). Cyclodextrins (CDs) are cyclic oligosaccharides that are capable of forming inclusion complexes with poorly soluble drugs, such as antioxidants. In this review, we discuss the use of CDs inclusion complexes to enhance the aqueous solubility of antioxidants and chemical UV filters and provide a protective shield against degradative factors. The role of CDs in providing a controlled drug release profile from sunscreens is also discussed. Finally, incorporating CDs inclusion complexes into sunscreens has the potential to increase their efficiency and hence improve their skin cancer prevention.

Solar ultraviolet-induced DNA damage response: Melanocytes story in transformation to environmental melanomagenesis.

Exposure to sunlight is both beneficial, as it heats the planet to a comfortable temperature, and potentially harmful, since sunlight contains ultraviolet radiation (UVR), which is deemed detrimental for living organisms. Earth's ozone layer plays a vital role in blocking most of the extremely dangerous UVC; however, low frequency/energy UVR (i.e., UVB and UVA) seeps through in minute amount and reaches the Earth's surface. Both UVB and UVA are physiologically responsible for a plethora of skin ailments, including skin cancers. The UVR is readily absorbed by the genomic DNA of skin cells, causing DNA bond distortion and UV-induced DNA damage. As a defense mechanism, the DNA damage response (DDR) signaling in skin cells activates nucleotide excision repair (NER), which is responsible for the removal of UVR-induced DNA photolesions and helps maintain the genomic integrity of the cells. Failure of proper NER function leads to mutagenesis and development of skin cancers. One of the deadliest form of skin cancers is melanoma which originates upon the genetic transformation of melanocytes, melanin producing skin cells. NER is a well-studied DNA repair system in the whole skin, as a tissue, but not much is known about it in melanocytes. Therefore, this review encapsulates NER in melanocytes, with a specific focus on its functional regulators and their cross talks due to skin heterogeneity and divulging the potential knowledge gap in the field.

Classification of Melanoma Skin Cancer using Convolutional Neural Network

Melanoma cancer is a type of skin cancer and is the most dangerous one because it causes the most of skin cancer deaths. Melanoma comes from melanocyte cells, melanin-producing cells, so that melanomas are generally brown or black coloured. Melanomas are mostly caused by exposure to ultraviolet radiation that damages the DNA of skin cells. The diagnoses of melanoma cancer are often performed manually by using visuals of the skilled doctors, analyzing the result of dermoscopy examination and match it with medical sciences. Manual detection weakness is highly influenced by human subjectivity that makes it inconsistent in certain conditions. Therefore, a computer assisted technology is needed to help classifying the results of dermoscopy examination and to deduce the results more accurately with a relatively faster time. The making of this application starts with problem analysis, design, implementation, and testing. This application uses deep learning technology with Convolutional Neural Network method and LeNet-5 architecture for classifying image data. The experiment using 44 images data from the training results with a different number of training and epoch resulted the highest percentage of success at 93% in training and 100% in testing, which the number of training data used of 176 images and 100 epochs. This application was created using Python programming language and Keras library as Tensorflow back-end.

Comprehensive Study to Decline the Burden of Skin Cancer

Skin cancer is the most common malignancy worldwide, including malignant melanoma and Non-malignant melanoma. The progressive increase in the incidence of skin cancers is observed, mainly in cutaneous melanomas over the last few decades. UV exposure is the most common cause of skin cancer, which occurs due to mutations in the DNA of skin cells. The mutation in MAPK pathway was the main cause of the skin cancer, in which BRAF gene undergoes 75 somatic mutations. The mutation in DNA suppressed the tumor suppressor gene p53, inactivates DNA repair gene and causes mutation in proto-oncogene results in the formation of oncogene which promote the cell growth, cell proliferation and cell reproduction by affecting the process of apoptosis. Skin cancer can be prevented by healthy dietary intervention and regular physical activity. In the current review, we highlight recent global trends in the treatments of skin cancer which involve chemotherapy, radiotherapy, photodynamic therapy, biological therapy and surgery. These therapies show the effectiveness by improving the survival rate and quality of life.

The role of the ATM/Chk/P53 pathway in mediating DNA damage in hand-foot syndrome induced by PLD

Pegylated liposomal doxorubicin (PLD) has been approved to treat patients with various types of cancers because it rarely caused side effects, such as cardiotoxicity, in comparison to doxorubicin, but it frequently results in hand-foot syndrome (HFS). This may affect the quality of life and require a reduction in the PLD dose. The pathophysiology of HFS was not well understood. This study was aimed at exploring the mechanism of HFS induced by PLD. We compared the effects of different doses of PLD on the proliferation inhibition and apoptosis in vitro in HaCaT cells and analyzed the skin changes and skin cell DNA damage in vivo using a zebrafish model. The results suggested that very low doses of PLD show a proliferation inhibition (cell cycle arrest at G2/M phase) and an apoptosis phenotype characterized by the ATM/Chk/P53 pathway that mediates DNA damage in vitro in HaCaT cells. In addition, PLD enhanced zebrafish skin pigmentation from the head to the trunk and induced DNA damage (phospho-H2AX staining) and cell death in the skin of zebrafish. The results of the present study suggested potential applications to provide a better understanding of the apoptosis of PLD-treated skin cells and described a simple methodology for detecting a PLD-induced DNA damage response in zebrafish, which may be helpful in preventing and treating HFS.

Ultraviolet Radiation‐Induced Skin Aging: The Role of DNA Damage and Oxidative Stress in Epidermal Stem Cell Damage Mediated Skin Aging

Skin is the largest human organ. Skin continually reconstructs itself to ensure its viability, integrity, and ability to provide protection for the body. Some areas of skin are continuously exposed to a variety of environmental stressors that can inflict direct and indirect damage to skin cell DNA. Skin homeostasis is maintained by mesenchymal stem cells in inner layer dermis and epidermal stem cells (ESCs) in the outer layer epidermis. Reduction of skin stem cell number and function has been linked to impaired skin homeostasis (e.g., skin premature aging and skin cancers). Skin stem cells, with self-renewal capability and multipotency, are frequently affected by environment. Ultraviolet radiation (UVR), a major cause of stem cell DNA damage, can contribute to depletion of stem cells (ESCs and mesenchymal stem cells) and damage of stem cell niche, eventually leading to photoinduced skin aging. In this review, we discuss the role of UV-induced DNA damage and oxidative stress in the skin stem cell aging in order to gain insights into the pathogenesis and develop a way to reduce photoaging of skin cells.

Modulation of Human Keratinocyte Responses to Solar UV by Plant Polyphenols As a Basis for Chemoprevention of Non-Melanoma Skin Cancers

Excessive exposure to solar UVA and UVB radiation is widely considered to cause skin cancers such as squamous cell carcinoma and basalioma. Direct UVB damage to skin cell DNA as well as UV-induced chronic skin inflammation, accelerated keratinocyte proliferation, inhibited apoptosis, and immunosuppression seem to underlie the UV-induced carcinogenesis. Also, UVB induces cytochrome P450 subfamilies (CYP1A1 and CYP1B1) involved in metabolic activation of organic pro-carcinogens and their conversion to ultimate carcinogens. Here, the effects of several glycosylated and non-glycosylated plant polyphenols (verbascoside, resveratrol, polydatin, rutin, and quercetin) on the inflammatory, apoptotic, metabolic, and proliferative responses of cultured human epidermal keratinocytes (HEK) to non-cytotoxic doses of solar-simulated UVA+UVB and chemical mediators of UV signalling in HEK, 6-formylindolo[3,2-b]carbazole and squalene isolated from photo-oxidized skin surface lipids (SSL), were evaluated. We showed that the stilbenes and quercetin being exposed to UV were photo-destroyed within a short period of time, while verbascoside and rutin were photo-stable. When SSL were exposed to UV, the stilbenes and quercetin remarkably accelerated photo-oxidation of alpha-tocopherol, squalene, and cholesterol fractions, whilst verbascoside protected them. Verbascoside invariably inhibited molecular pathways in HEK leading to inflammatory cytokine expression (NFkappaB and EGFR/ERK phosphorylation), and cell proliferation (EGFR nuclear translocation), and displayed a stimulus-specific effect on the metabolic axis aryl hydrocarbon receptor (AhR)-CYP1A1/CYP1B1. By contrast, the stilbenes inhibited UV-connected inflammatory cytokines excluding IL-8, but they prevalently stimulated NFkappaB, EGFR nuclear translocation and the AhR-CYP pathway. We conclude that, among the PPs investigated, verbascoside does interfere with multiple UV-sensitive signalling in HEK in a way that it could have a major impact on skin cancer chemoprevention.

Highly Potent Activation of Nrf2 by Topical Tricyclic Bis(Cyano Enone): Implications for Protection against UV Radiation during Thiopurine Therapy

Chronic treatment with azathioprine, a highly effective anti-inflammatory and immunosuppressive agent, profoundly increases the risk for development of unusually aggressive cutaneous squamous cell carcinoma. Its ultimate metabolite, 6-thioguanine (6-TG) nucleotide, is incorporated in DNA of skin cells, and upon exposure to UVA radiation, causes oxidative stress, followed by damage of DNA and associated proteins. The acetylenic tricyclic bis(cyano enone) TBE-31 is a strong inhibitor of inflammation and a potent inducer of the Keap1/Nrf2/ARE pathway, which orchestrates the expression of a large network of cytoprotective genes. We now report that long-term (five days per week for four weeks) topical daily applications of small (200 nmol) quantities of TBE-31 cause a robust systemic induction of the Keap1/Nrf2/ARE pathway and decreases the 6-TG incorporation in DNA of skin, blood, and liver of azathioprine-treated mice, indicating extraordinary bioavailability and efficacy. In addition, TBE-31, at nanomolar concentrations, protects cells with 6-TG in their genomic DNA against oxidative stress caused by UVA radiation through induction of the Keap1/Nrf2/ARE pathway. At the same 6-TG DNA levels, Keap1-knockout cells, in which the pathway is constitutively upregulated, are highly resistant to UVA radiation-induced oxidative stress. The protective effects of both the Keap1-knockout genotype and TBE-31 are completely lost in the absence of transcription factor Nrf2. Our findings suggest that compounds of this kind are excellent candidates for mechanism-based chemoprotective agents against conditions in which oxidative stress and inflammation underlie disease pathogenesis. Moreover, their potential skin patch incorporation for transdermal delivery is an exciting possibility.

A Community-Based Study of Nucleotide Excision Repair Polymorphisms in Relation to the Risk of Non-Melanoma Skin Cancer

Nucleotide excision repair (NER) is responsible for protecting DNA in skin cells against ultraviolet radiation-induced damage. Using a candidate pathway approach, a matched case-control study nested within a prospective, community-based cohort was carried out to test the hypothesis that single nucleotide polymorphisms (SNPs) in NER genes are associated with susceptibility to non-melanoma skin cancer (NMSC). Histologically-confirmed cases of NMSC (n=900) were matched to controls (n=900) on age, gender, and skin type. Associations were measured between NMSC and 221 SNPs in 26 NER genes. Using the additive model, two tightly linked functional SNPs in ERCC6 were significantly associated with increased risk of NMSC: rs2228527 (odds ratio (OR) 1.57, 95% confidence interval (CI) 1.20 – 2.05), and rs2228529 (OR 1.57, 95% CI 1.20 – 2.05). These associations were confined to basal cell carcinoma of the skin (BCC) (rs2228529, OR 1.78, 95% CI 1.30 – 2.44; rs2228527 OR 1.78, 95% CI 1.31 – 2.43). These hypothesis-generating findings suggest functional variants in ERCC6 may be associated with an increased risk of NMSC that may be specific to BCC.