Melanocytes: Mammalian pigment cells that produce MELANINS, pigments found mainly in the EPIDERMIS, but also in the eyes and the hair, by a process called melanogenesis. Coloration can be altered by the number of melanocytes or the amount of pigment produced and stored in the organelles called MELANOSOMES. The large non-mammalian melanin-containing cells are called MELANOPHORES.Melanins: Insoluble polymers of TYROSINE derivatives found in and causing darkness in skin (SKIN PIGMENTATION), hair, and feathers providing protection against SUNBURN induced by SUNLIGHT. CAROTENES contribute yellow and red coloration.Vitiligo: A disorder consisting of areas of macular depigmentation, commonly on extensor aspects of extremities, on the face or neck, and in skin folds. Age of onset is often in young adulthood and the condition tends to progress gradually with lesions enlarging and extending until a quiescent state is reached.Monophenol Monooxygenase: An enzyme of the oxidoreductase class that catalyzes the reaction between L-tyrosine, L-dopa, and oxygen to yield L-dopa, dopaquinone, and water. It is a copper protein that acts also on catechols, catalyzing some of the same reactions as CATECHOL OXIDASE. EC 1.14.18.1.Melanosomes: Melanin-containing organelles found in melanocytes and melanophores.Skin Pigmentation: Coloration of the skin.Melanoma: A malignant neoplasm derived from cells that are capable of forming melanin, which may occur in the skin of any part of the body, in the eye, or, rarely, in the mucous membranes of the genitalia, anus, oral cavity, or other sites. It occurs mostly in adults and may originate de novo or from a pigmented nevus or malignant lentigo. Melanomas frequently metastasize widely, and the regional lymph nodes, liver, lungs, and brain are likely to be involved. The incidence of malignant skin melanomas is rising rapidly in all parts of the world. (Stedman, 25th ed; from Rook et al., Textbook of Dermatology, 4th ed, p2445)Microphthalmia-Associated Transcription Factor: A basic helix-loop-helix leucine zipper transcription factor that regulates the CELL DIFFERENTIATION and development of a variety of cell types including MELANOCYTES; OSTEOCLASTS; and RETINAL PIGMENT EPITHELIUM. Mutations in MITF protein have been associated with OSTEOPETROSIS and WAARDENBURG SYNDROME.Pigmentation: Coloration or discoloration of a part by a pigment.Hair Color: Color of hair or fur.Skin Neoplasms: Tumors or cancer of the SKIN.Nevus: A circumscribed stable malformation of the skin and occasionally of the oral mucosa, which is not due to external causes and therefore presumed to be of hereditary origin.Pancreatic Neoplasms: Tumors or cancer of the PANCREAS. Depending on the types of ISLET CELLS present in the tumors, various hormones can be secreted: GLUCAGON from PANCREATIC ALPHA CELLS; INSULIN from PANCREATIC BETA CELLS; and SOMATOSTATIN from the SOMATOSTATIN-SECRETING CELLS. Most are malignant except the insulin-producing tumors (INSULINOMA).Neoplasms: New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.alpha-MSH: A 13-amino acid peptide derived from proteolytic cleavage of ADRENOCORTICOTROPIC HORMONE, the N-terminal segment of ACTH. ACTH (1-13) is amidated at the C-terminal to form ACTH (1-13)NH2 which in turn is acetylated to form alpha-MSH in the secretory granules. Alpha-MSH stimulates the synthesis and distribution of MELANIN in MELANOCYTES in mammals and MELANOPHORES in lower vertebrates.Endothelin-3: A 21-amino acid peptide that circulates in the plasma, but its source is not known. Endothelin-3 has been found in high concentrations in the brain and may regulate important functions in neurons and astrocytes, such as proliferation and development. It also is found throughout the gastrointestinal tract and in the lung and kidney. (N Eng J Med 1995;333(6):356-63)Hypopigmentation: A condition caused by a deficiency or a loss of melanin pigmentation in the epidermis, also known as hypomelanosis. Hypopigmentation can be localized or generalized, and may result from genetic defects, trauma, inflammation, or infections.Neoplasms, Cystic, Mucinous, and Serous: Neoplasms containing cyst-like formations or producing mucin or serum.Skin: The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.Intramolecular Oxidoreductases: Enzymes of the isomerase class that catalyze the oxidation of one part of a molecule with a corresponding reduction of another part of the same molecule. They include enzymes converting aldoses to ketoses (ALDOSE-KETOSE ISOMERASES), enzymes shifting a carbon-carbon double bond (CARBON-CARBON DOUBLE BOND ISOMERASES), and enzymes transposing S-S bonds (SULFUR-SULFUR BOND ISOMERASES). (From Enzyme Nomenclature, 1992) EC 5.3.Pigmentation DisordersEpidermis: The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of EPITHELIUM: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis).Hyperpigmentation: Excessive pigmentation of the skin, usually as a result of increased epidermal or dermal melanin pigmentation, hypermelanosis. Hyperpigmentation can be localized or generalized. The condition may arise from exposure to light, chemicals or other substances, or from a primary metabolic imbalance.Melanocyte-Stimulating Hormones: Peptides with the ability to stimulate pigmented cells MELANOCYTES in mammals and MELANOPHORES in lower vertebrates. By stimulating the synthesis and distribution of MELANIN in these pigmented cells, they increase coloration of skin and other tissue. MSHs, derived from pro-opiomelanocortin (POMC), are produced by MELANOTROPHS in the INTERMEDIATE LOBE OF PITUITARY; CORTICOTROPHS in the ANTERIOR LOBE OF PITUITARY, and the hypothalamic neurons in the ARCUATE NUCLEUS OF HYPOTHALAMUS.Proto-Oncogene Proteins c-kit: A protein-tyrosine kinase receptor that is specific for STEM CELL FACTOR. This interaction is crucial for the development of hematopoietic, gonadal, and pigment stem cells. Genetic mutations that disrupt the expression of PROTO-ONCOGENE PROTEINS C-KIT are associated with PIEBALDISM, while overexpression or constitutive activation of the c-kit protein-tyrosine kinase is associated with tumorigenesis.Nevus, Pigmented: A nevus containing melanin. The term is usually restricted to nevocytic nevi (round or oval collections of melanin-containing nevus cells occurring at the dermoepidermal junction of the skin or in the dermis proper) or moles, but may be applied to other pigmented nevi.Agouti Signaling Protein: A secreted protein of approximately 131 amino acids (depending on species) that regulates the synthesis of eumelanin (brown/black) pigments in MELANOCYTES. Agouti protein antagonizes the signaling of MELANOCORTIN RECEPTORS and has wide distribution including ADIPOSE TISSUE; GONADS; and HEART. Its overexpression in agouti mice results in uniform yellow coat color, OBESITY, and metabolic defects similar to type II diabetes in humans.Uvea: The pigmented vascular coat of the eyeball, consisting of the CHOROID; CILIARY BODY; and IRIS, which are continuous with each other. (Cline et al., Dictionary of Visual Science, 4th ed)Receptor, Melanocortin, Type 1: A melanocortin receptor subtype found primarily in MELANOCYTES. It shows specificity for ALPHA-MSH and ADRENOCORTICOTROPIC HORMONE. Loss of function mutations of the type 1 melanocortin receptor account for the majority of red hair and fair skin recessive traits in human.Neoplasms, Multiple Primary: Two or more abnormal growths of tissue occurring simultaneously and presumed to be of separate origin. The neoplasms may be histologically the same or different, and may be found in the same or different sites.Neural Crest: The two longitudinal ridges along the PRIMITIVE STREAK appearing near the end of GASTRULATION during development of nervous system (NEURULATION). The ridges are formed by folding of NEURAL PLATE. Between the ridges is a neural groove which deepens as the fold become elevated. When the folds meet at midline, the groove becomes a closed tube, the NEURAL TUBE.Hermanski-Pudlak Syndrome: Syndrome characterized by the triad of oculocutaneous albinism (ALBINISM, OCULOCUTANEOUS); PLATELET STORAGE POOL DEFICIENCY; and lysosomal accumulation of ceroid lipofuscin.Ultraviolet Rays: That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Hair Follicle: A tube-like invagination of the EPIDERMIS from which the hair shaft develops and into which SEBACEOUS GLANDS open. The hair follicle is lined by a cellular inner and outer root sheath of epidermal origin and is invested with a fibrous sheath derived from the dermis. (Stedman, 26th ed) Follicles of very long hairs extend into the subcutaneous layer of tissue under the SKIN.Keratinocytes: Epidermal cells which synthesize keratin and undergo characteristic changes as they move upward from the basal layers of the epidermis to the cornified (horny) layer of the skin. Successive stages of differentiation of the keratinocytes forming the epidermal layers are basal cell, spinous or prickle cell, and the granular cell.Antigens, Neoplasm: Proteins, glycoprotein, or lipoprotein moieties on surfaces of tumor cells that are usually identified by monoclonal antibodies. Many of these are of either embryonic or viral origin.PhenylthioureaNeoplasm Proteins: Proteins whose abnormal expression (gain or loss) are associated with the development, growth, or progression of NEOPLASMS. Some neoplasm proteins are tumor antigens (ANTIGENS, NEOPLASM), i.e. they induce an immune reaction to their tumor. Many neoplasm proteins have been characterized and are used as tumor markers (BIOMARKERS, TUMOR) when they are detectable in cells and body fluids as monitors for the presence or growth of tumors. Abnormal expression of ONCOGENE PROTEINS is involved in neoplastic transformation, whereas the loss of expression of TUMOR SUPPRESSOR PROTEINS is involved with the loss of growth control and progression of the neoplasm.SOXE Transcription Factors: A subclass of closely-related SOX transcription factors. Members of this subfamily have been implicated in regulating the differentiation of OLIGODENDROCYTES during neural crest formation and in CHONDROGENESIS.Kidney Neoplasms: Tumors or cancers of the KIDNEY.Stem Cell Factor: A hematopoietic growth factor and the ligand of the cell surface c-kit protein (PROTO-ONCOGENE PROTEINS C-KIT). It is expressed during embryogenesis and is a growth factor for a number of cell types including the MAST CELLS and the MELANOCYTES in addition to the HEMATOPOIETIC STEM CELLS.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Neoplasms, Second Primary: Abnormal growths of tissue that follow a previous neoplasm but are not metastases of the latter. The second neoplasm may have the same or different histological type and can occur in the same or different organs as the previous neoplasm but in all cases arises from an independent oncogenic event. The development of the second neoplasm may or may not be related to the treatment for the previous neoplasm since genetic risk or predisposing factors may actually be the cause.gp100 Melanoma Antigen: A melanosome-associated protein that plays a role in the maturation of the MELANOSOME.MART-1 Antigen: A melanosome-specific protein that plays a role in the expression, stability, trafficking, and processing of GP100 MELANOMA ANTIGEN, which is critical to the formation of Stage II MELANOSOMES. The protein is used as an antigen marker for MELANOMA cells.Chromatophores: The large pigment cells of fish, amphibia, reptiles and many invertebrates which actively disperse and aggregate their pigment granules. These cells include MELANOPHORES, erythrophores, xanthophores, leucophores and iridiophores. (In algae, chromatophores refer to CHLOROPLASTS. In phototrophic bacteria chromatophores refer to membranous organelles (BACTERIAL CHROMATOPHORES).)Catechol Oxidase: An enzyme of the oxidoreductase class that catalyzes the reaction between catechol and oxygen to yield benzoquinone and water. It is a complex of copper-containing proteins that acts also on a variety of substituted catechols. EC 1.10.3.1.Melanoma, Experimental: Experimentally induced tumor that produces MELANIN in animals to provide a model for studying human MELANOMA.Piebaldism: Autosomal dominant, congenital disorder characterized by localized hypomelanosis of the skin and hair. The most familiar feature is a white forelock presenting in 80 to 90 percent of the patients. The underlying defect is possibly related to the differentiation and migration of melanoblasts, as well as to defective development of the neural crest (neurocristopathy). Piebaldism may be closely related to WAARDENBURG SYNDROME.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.Adenocarcinoma, Mucinous: An adenocarcinoma producing mucin in significant amounts. (From Dorland, 27th ed)Thyroid Neoplasms: Tumors or cancer of the THYROID GLAND.DNA, Neoplasm: DNA present in neoplastic tissue.Myeloproliferative Disorders: Conditions which cause proliferation of hemopoietically active tissue or of tissue which has embryonic hemopoietic potential. They all involve dysregulation of multipotent MYELOID PROGENITOR CELLS, most often caused by a mutation in the JAK2 PROTEIN TYROSINE KINASE.Receptors, Melanocortin: A family of G-protein-coupled receptors that have specificity for MELANOCYTE-STIMULATING HORMONES and ADRENOCORTICOTROPIC HORMONE. There are several subtypes of melanocortin receptors, each having a distinct ligand specificity profile and tissue localization.Eye Neoplasms: Tumors or cancer of the EYE.Melanosis: Disorders of increased melanin pigmentation that develop without preceding inflammatory disease.Lung Neoplasms: Tumors or cancer of the LUNG.Parotid Neoplasms: Tumors or cancer of the PAROTID GLAND.Cystadenoma: A benign neoplasm derived from glandular epithelium, in which cystic accumulations of retained secretions are formed. In some instances, considerable portions of the neoplasm, or even the entire mass, may be cystic. (Stedman, 25th ed)Neoplasms, Connective and Soft Tissue: Neoplasms developing from some structure of the connective and subcutaneous tissue. The concept does not refer to neoplasms located in connective or soft tissue.Neoplasms, Plasma Cell: Neoplasms associated with a proliferation of a single clone of PLASMA CELLS and characterized by the secretion of PARAPROTEINS.Receptors, Corticotropin: Cell surface receptors that bind CORTICOTROPIN; (ACTH, adrenocorticotropic hormone) with high affinity and trigger intracellular changes. Pharmacology suggests there may be multiple ACTH receptors. An ACTH receptor has been cloned and belongs to a subfamily of G-protein-coupled receptors. In addition to the adrenal cortex, ACTH receptors are found in the brain and immune systems.Appendiceal Neoplasms: Tumors or cancer of the APPENDIX.Neoplasms, Experimental: Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.Liver Neoplasms: Tumors or cancer of the LIVER.Melanoma-Specific Antigens: Cellular antigens that are specific for MELANOMA cells.Albinism, Oculocutaneous: Heterogeneous group of autosomal recessive disorders comprising at least four recognized types, all having in common varying degrees of hypopigmentation of the skin, hair, and eyes. The two most common are the tyrosinase-positive and tyrosinase-negative types.Neoplasms, Radiation-Induced: Tumors, cancer or other neoplasms produced by exposure to ionizing or non-ionizing radiation.Cystadenoma, Mucinous: A multilocular tumor with mucin secreting epithelium. They are most often found in the ovary, but are also found in the pancreas, appendix, and rarely, retroperitoneal and in the urinary bladder. They are considered to have low-grade malignant potential.Ovarian Neoplasms: Tumors or cancer of the OVARY. These neoplasms can be benign or malignant. They are classified according to the tissue of origin, such as the surface EPITHELIUM, the stromal endocrine cells, and the totipotent GERM CELLS.Endocrine Gland Neoplasms: Tumors or cancer of the ENDOCRINE GLANDS.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.Neoplasm Invasiveness: Ability of neoplasms to infiltrate and actively destroy surrounding tissue.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Gastrointestinal Neoplasms: Tumors or cancer of the GASTROINTESTINAL TRACT, from the MOUTH to the ANAL CANAL.Carcinoma, Pancreatic Ductal: Carcinoma that arises from the PANCREATIC DUCTS. It accounts for the majority of cancers derived from the PANCREAS.Neoplasms, Vascular Tissue: Neoplasms composed of vascular tissue. This concept does not refer to neoplasms located in blood vessels.Oxidoreductases: The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)Uveal Neoplasms: Tumors or cancer of the UVEA.Myosin Type V: A subclass of myosin involved in organelle transport and membrane targeting. It is abundantly found in nervous tissue and neurosecretory cells. The heavy chains of myosin V contain unusually long neck domains that are believed to aid in translocating molecules over large distances.Nose Neoplasms: Tumors or cancer of the NOSE.Salivary Gland Neoplasms: Tumors or cancer of the SALIVARY GLANDS.Tumor Markers, Biological: Molecular products metabolized and secreted by neoplastic tissue and characterized biochemically in cells or body fluids. They are indicators of tumor stage and grade as well as useful for monitoring responses to treatment and predicting recurrence. Many chemical groups are represented including hormones, antigens, amino and nucleic acids, enzymes, polyamines, and specific cell membrane proteins and lipids.Tumor Cells, Cultured: Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.Stem Cells: Relatively undifferentiated cells that retain the ability to divide and proliferate throughout postnatal life to provide progenitor cells that can differentiate into specialized cells.Adenocarcinoma, Papillary: An adenocarcinoma containing finger-like processes of vascular connective tissue covered by neoplastic epithelium, projecting into cysts or the cavity of glands or follicles. It occurs most frequently in the ovary and thyroid gland. (Stedman, 25th ed)Carcinoma, Papillary: A malignant neoplasm characterized by the formation of numerous, irregular, finger-like projections of fibrous stroma that is covered with a surface layer of neoplastic epithelial cells. (Stedman, 25th ed)Testicular Neoplasms: Tumors or cancer of the TESTIS. Germ cell tumors (GERMINOMA) of the testis constitute 95% of all testicular neoplasms.Neoplasms, Muscle Tissue: Neoplasms composed of muscle tissue: skeletal, cardiac, or smooth. The concept does not refer to neoplasms located in muscles.Neoplasms, Glandular and Epithelial: Neoplasms composed of glandular tissue, an aggregation of epithelial cells that elaborate secretions, and of any type of epithelium itself. The concept does not refer to neoplasms located in the various glands or in epithelial tissue.Neoplasm Staging: Methods which attempt to express in replicable terms the extent of the neoplasm in the patient.Melanoma, Amelanotic: An unpigmented malignant melanoma. It is an anaplastic melanoma consisting of cells derived from melanoblasts but not forming melanin. (Dorland, 27th ed; Stedman, 25th ed)Cystadenocarcinoma, Mucinous: A malignant cystic or semisolid tumor most often occurring in the ovary. Rarely, one is solid. This tumor may develop from a mucinous cystadenoma, or it may be malignant at the onset. The cysts are lined with tall columnar epithelial cells; in others, the epithelium consists of many layers of cells that have lost normal structure entirely. In the more undifferentiated tumors, one may see sheets and nests of tumor cells that have very little resemblance to the parent structure. (Hughes, Obstetric-Gynecologic Terminology, 1972, p184)Adenoma: A benign epithelial tumor with a glandular organization.Mice, Inbred C57BLSoft Tissue Neoplasms: Neoplasms of whatever cell type or origin, occurring in the extraskeletal connective tissue framework of the body including the organs of locomotion and their various component structures, such as nerves, blood vessels, lymphatics, etc.Hematologic Neoplasms: Neoplasms located in the blood and blood-forming tissue (the bone marrow and lymphatic tissue). The commonest forms are the various types of LEUKEMIA, of LYMPHOMA, and of the progressive, life-threatening forms of the MYELODYSPLASTIC SYNDROMES.Uterine Neoplasms: Tumors or cancer of the UTERUS.Intestinal Neoplasms: Tumors or cancer of the INTESTINES.Neoplasms, Adnexal and Skin Appendage: Neoplasms composed of sebaceous or sweat gland tissue or tissue of other skin appendages. The concept does not refer to neoplasms located in the sebaceous or sweat glands or in the other skin appendages.
A stimulation of melanin synthesis within iris melanocytes has been postulated.[medical citation needed] Neoplasm - Nevi and ... Neoplasm - Melanomas can also be very lightly pigmented, and a lighter colored iris may be a rare manifestation of metastatic ... The affected sectors have been shown to have reduced numbers of melanocytes and decreased stromal pigmentation. Incontinentia ... Piebaldism - similar to Waardenburg's syndrome, a rare disorder of melanocyte development characterized by a white forelock and ...
In poliosis there is decreased or absent melanin in the hair bulbs of affected hair follicles; the melanocytes of the skin are ... and in association with neoplasms and some medications. It can give rise to a "Mallen streak" that can be hereditary. Catherine ...
Melanocytic nevi and neoplasms are caused by either a proliferation of (1) melanocytes, or (2) nevus cells, a form of ... may be related to loss of melanocytes or the inability of melanocytes to produce melanin or transport melanosomes correctly. ... CS1 maint: Multiple names: authors list (link) Costin GE, Hearing VJ; Hearing (2007). "Human skin pigmentation: melanocytes ... The epidermis contains four cell types: keratinocytes, melanocytes, Langerhans cells, and Merkel cells. Of these, keratinocytes ...
... is due as a result of malignant melanocytes. This occurs at the membrane of the skin (outer layers ... Shea, Christopher R.; Reed, Jon A.; Prieto, Victor G. (2014-11-03). Pathology of Challenging Melanocytic Neoplasms: Diagnosis ... Hearing, Vincent J.; Leong, Stanley P. L. (2007-11-05). From Melanocytes to Melanoma: The Progression to Malignancy. Springer ... Melanoma is a potentially serious skin cancer that arises from pigment cells (melanocytes). Although acral lentiginous melanoma ...
Benign neoplasms are typically but not always composed of cells which bear a strong resemblance to a normal cell type in their ... or melanocytes) and seminoma (a cancer of male reproductive cells). Skin tags, vocal chord polyps and hyperplastic polyps of ... ISBN 92-832-2416-7. Gill SS, Heuman DM, Mihas AA (October 2001). "Small intestinal neoplasms". J. Clin. Gastroenterol. 33 (4): ... the colon are often referred to as benign but they are actually overgrowths of normal tissue rather than neoplasms. Benign ...
The defect is thought to cause a proliferation of melanocytes. This means melanocytes, the cells in the body in charge of ... Acquired moles are a form of benign neoplasm, while congenital moles, or congenital nevi, are considered a minor malformation ... Thus causing the melanocytes to form in clusters instead of spread out, causing abnormal skin pigmentation in some areas of the ... Blue nevus: It is blue in color as its melanocytes are very deep in the skin. The nevus cells are spindle shaped and scattered ...
The MART-1/melan-A antigen is specific for the melanocyte lineage, found in normal skin, the retina, and melanocytes, but not ... Ghorab Z, Jorda M, Ganjei P, Nadji M (2004). "Melan A (A103) is expressed in adrenocortical neoplasms but not in renal cell and ... of Belgium called the gene melan-A, presumably an abbreviation for "melanocyte antigen." MART-1/melan-A is a protein antigen ... 2003). "MLANA/MART1 and SILV/PMEL17/GP100 are transcriptionally regulated by MITF in melanocytes and melanoma". Am. J. Pathol. ...
Diseases of the skin include skin infections and skin neoplasms (including skin cancer). In 1572, Geronimo Mercuriali of Forlì ... The epidermis contains four cell types: keratinocytes, melanocytes, Langerhans cells, and Merkel cells. Of these, keratinocytes ...
These enhance angiogenesis and aid in the growth of UV-induced neoplasms. It has been reported that UV radiation leads to local ... The epidermal layer does not contain any blood vessels or nerve endings but melanocytes and basal cells are embedded in this ... Upon exposure to UVB rays, melanocytes will produce melanin, a pigment that gives the skin its color tone. However, UVB will ...
It then causes melanocytes to produce more pigment, thus darkening the skin tone. The standard treatment for Addison's disease ... Low, G., & Sahi, K. (2012). Clinical and imaging overview of functional adrenal neoplasms. International Journal of Urology, 19 ... the pituitary gland continues to secrete corticotropin which binds to the receptor for melanocyte-stimulating hormone. ...
... melanocyte - melanoma - melanoma vaccine - melphalan - MEN-10755 - MEN1 syndrome - meningeal - meningeal metastases - ... neoplasm - nephrotomogram - nephrotoxic - nephroureterectomy - nerve block - nerve grafting - nerve-sparing radical ... Hürthle cell neoplasm - hydrazine sulfate - hydromorphone - hydronephrosis - hydroureter - hydroxychloroquine - hydroxyurea - ...
Melanocytes. Nevus Meninges. Meningioma Nerve cells. Ganglioneuroma Reference[31]. Benign neoplasms are typically but not ... Gill SS, Heuman DM, Mihas AA (October 2001). "Small intestinal neoplasms". J. Clin. Gastroenterol. 33 (4): 267-82. doi:10.1097/ ... or melanocytes) and seminoma (a cancer of male reproductive cells).[32] Skin tags, vocal chord polyps and hyperplastic polyps ... of the colon are often referred to as benign but they are actually overgrowths of normal tissue rather than neoplasms.[4] ...
... melanocytes) that reside within the uvea giving color to the eye. These melanocytes are distinct from the retinal pigment ... Kumar, Vinay (2009). "Uvea: Neoplasms". Robbins and Cotran Pathologic Basis of Disease, Professional Edition (8th ed.). ... Uveal tumors can originate from melanocytes residing within the iris. Benign melanocytic tumors, such as iris freckles and ... Though derived from uveal melanocytes, iris melanomas share more in common with cutaneous (skin) melanomas, in that they ...
Sarcoids are the most common type of skin neoplasm and are the most common type of cancer overall in horses. Squamous-cell ... Equine melanoma results from abnormal proliferation and accumulation of melanocytes, pigmented cells within the dermis. Gray ... making it the most common neoplasm reported in older horses. Carcinomas are tumors derived from epithelial cells and SCC ...
... s (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. GISTs arise in ... melanocytes and several others. In the gut, however, a mass staining positive for CD117 is likely to be a GIST, arising from ...
Melanin is produced within the skin in cells called melanocytes and it is the main determinant of the skin color of darker- ... Diseases of the skin include skin infections and skin neoplasms (including skin cancer). Dermatology is the branch of medicine ... The average square inch (6.5 cm²) of skin holds 650 sweat glands, 20 blood vessels, 60,000 melanocytes, and more than 1,000 ... The main type of cells which make up the epidermis are Merkel cells, keratinocytes, with melanocytes and Langerhans cells also ...
These lesions arise from melanocytes, the cells that give skin color and are most common in Caucasian women 50-80 years old. ... "Vulvar Cancer". Gynecologic Neoplasms. Armenian Health Network, Health.am. 2005. Retrieved 2007-11-08. International Federation ...
... skin melanocytes". Domestic Animal Endocrinology. 38 (3): 200-209. doi:10.1016/j.domaniend.2009.10.004. PMID 20036482. ... "MicroRNA expression pattern in intraductal papillary mucinous neoplasm". The Korean journal of gastroenterology = Taehan ...
Diseases of the skin include skin infections and skin neoplasms (including skin cancer).[28] ... melanocytes, Langerhans cells, and Merkel cells. Of these, keratinocytes are the major component, constituting roughly 95% of ...
The term nevus is applied to a number of conditions caused by neoplasias and hyperplasias of melanocytes,[2] as well as a ... Tumors: Skin neoplasm, nevi and melanomas (C43/D22, 172/216, ICD-O 8720-8799) ... Benign Neoplasias and Hyperplasias of Melanocytes". Fitzpatrick's Dermatology in General Medicine. The McGraw-Hill Companies, ... Additional types of nevi do not involve disorders of pigmentation or melanocytes. These additional nevi represent hamartomatous ...
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... neoplasms including sarcomas such as hemangiopericytoma and malignant peripheral nerve sheath tumor in ...
The earliest stage of melanoma starts when melanocytes begin out-of-control growth. Melanocytes are found between the outer ... Tumors: Skin neoplasm, nevi and melanomas (C43/D22, 172/216, ICD-O 8720-8799) ... and against fetal melanocytes but not normal adult melanocytes. ... denoting a tissue mass and especially a neoplasm), in turn from ... is a type of cancer that develops from the pigment-containing cells known as melanocytes.[1] Melanomas typically occur in the ...
A benign neoplasm composed of melanocytes.. *. A usually benign, deeply pigmented melanoma of the optic disk. ...
Lip Neoplasms / chemistry, pathology*, therapy. Male. Melanocytes / chemistry, pathology. Melanoma / chemistry, pathology*, ... Neoplasms, Multiple Primary / pathology*, therapy. Skin Neoplasms / chemistry, pathology*, therapy. Tumor Markers, Biological ... An immunohistochemical panel showed that the spindle cells were melanocytes, not derived from the squamous cell carcinoma. ... which also showed sparse melanocyte atypia within the epidermis and an extensive spindle cell proliferation within the dermis, ...
The neoplasm arises from melanocytes in a complex process. In each CMM, the tumour size is closely associated with cell ... They vary according to the histopathologic type and progression stage of the neoplasm including metastasis. The location of the ... nonneoplastic melanocytes do not express HOX-D3. HOX-D12 and -D13 were reported to be expressed in CMM at a higher level than ... "Immunohistochemical aid at risk stratification of melanocytic neoplasms," International journal of oncology, vol. 24, no. 1, pp ...
A stimulation of melanin synthesis within iris melanocytes has been postulated.[medical citation needed] Neoplasm - Nevi and ... Neoplasm - Melanomas can also be very lightly pigmented, and a lighter colored iris may be a rare manifestation of metastatic ... The affected sectors have been shown to have reduced numbers of melanocytes and decreased stromal pigmentation. Incontinentia ... Piebaldism - similar to Waardenburgs syndrome, a rare disorder of melanocyte development characterized by a white forelock and ...
... has led to the hypothesis that melanocytes derived from the neural crest may be arrested in their migration and may undergo an ... Melanocytes / enzymology* * Melanoma / enzymology* * Molecular Sequence Data * Monophenol Monooxygenase / genetics* * Neoplasms ... The occasional occurrence of primary extra-cutaneous malignant melanomas (MM) has led to the hypothesis that melanocytes ... one could propose that they might correspond to either fully differentiated melanocytes, melanocytic precursors, or Schwann ...
Pigmented lesions of the eyelids arise from 1 of 3 types of melanocytes, as follows: (1) epidermal or dendritic melanocytes, (2 ... Margin tumors should arouse the suspicion of a conjunctival neoplasm. The propensity of pigmented lesions to arise on the ... Melanocytes are melanin-producing cells found in the basal cell layer of the epidermis. Nevus cells are incompletely ... Melanomas arise from epidermal melanocytes and represent less than 1% of all eyelid tumors. It can occur in 1 of the 3 ...
It is well known that melanoma is a malignant neoplasm arising from the melanocytes, cells of neuro-ectodermal origin, which ... J. M. Carubia, R. K. Yu, and L. J. Macala, "Gangliosides of normal and neoplastic human melanocytes," Biochemical and ... This recognition was located in the plasmatic membrane and also in the cytoplasm of more than 50% of melanocytes (Figure 1). No ... The staining was located mainly in the plasmatic membrane and also in the cytoplasm of melanocytes (data no shown). When the ...
Iris Neoplasms. Tumors of the iris characterized by increased pigmentation of melanocytes. Iris nevi are composed of ... It is a pigmented lesion composed of melanocytes occurring on sun-exposed skin, usually the face and neck. The melanocytes are ... Melanoma is a highly malignant tumor of melanin-forming cells (melanocytes) There are most commonly found in the skin ( ... proliferated melanocytes and are associated with neurofibromatosis and malignant melanoma of the choroid and ciliary body. ...
Iris Neoplasms. Tumors of the iris characterized by increased pigmentation of melanocytes. Iris nevi are composed of ... It is a pigmented lesion composed of melanocytes occurring on sun-exposed skin, usually the face and neck. The melanocytes are ... proliferated melanocytes and are associated with neurofibromatosis and malignant melanoma of the choroid and ciliary body. ...
... is a neoplasm of melanocytes or a neoplasm of the cells that develop from melanocytes. Although it was once considered uncommon ... Malignant melanoma (see the image below) is a neoplasm of melanocytes or a neoplasm of the cells that develop from melanocytes ... Malignant melanoma is a neoplasm of melanocytes or of the cells that develop from melanocytes. (See the images below.) Although ... induction of melanocyte cell division, free radical production, and damage of melanocyte DNA. ...
This refers to any benign congenital or acquired neoplasm of melanocytes. Melanocytic nevus(TOPNOTCH)Robbins Basic Pathology, ... In albinism, melanocytes are present but melanin pigment is not produced due to what enzyme deficiency or defect? ... Her lesion (A) is a tumor of malignant melanocytes (B) is common in her age group (C) will exhibit a fishnet appearance if ... Q: + for melanocyte-associated proteins such as tyrosinase or Melan-A or S ...
2) ⇓ , but the low number of melanocytes in the basal layer (one melanocyte every 10-15 kera tinocytes) may mask any effect. ... Elder D. E. Human melanocytic neoplasms and their etiologic relationship with sunlight. J. Investig. Dermatol., 92: 297S-303S, ... An alternative explanation is that the effects on the keratinocytes are mediated by melanocytes. The basal layer melanocytes ... α-MSH also has a proliferative effect on melanocytes (10 , 11) . The biological action of α-MSH on melanocytes is mediated ...
neoplasm composed of abnormal melanocytes appearing in both the epidermis and dermis. malignant melanoma. ...
Melanoma is a very aggressive neoplasm with a propensity to undergo progression and invasion early in its evolution. The ... Melanoma is a very aggressive neoplasm with a propensity to undergo progression and invasion early in its evolution. The ... Melanoma is a malignant neoplasm of the neural crest-derived melanocytes, the pigment-producing cells. Approximately 65% of ... including melanocyte progenitors (2). PAX3 is expressed in melanoma tissues and cell lines, melanocyte cell lines (3, 4), and ...
Melanocytes / metabolism, pathology. Melanoma / genetics*, pathology, surgery. Microsatellite Repeats. Receptors, Cell Surface ... Skin Neoplasms / genetics, pathology, surgery. Chemical. Reg. No./Substance: 0/Agglutinins; 0/DMBT1 protein, human; 0/DNA ...
... malignant melanocytes can be reprogrammed into mesenchymal-like cells through a process similar to epithelial-mesenchymal ... Melanocytes / metabolism * Melanoma / genetics* * Melanoma / metabolism* * Melanoma / pathology * Neoplasm Invasiveness * ... Recent evidence supports a role for SLUG, a transcriptional repressor of E-cadherin, as a melanocyte lineage transcription ... During progression of melanoma, malignant melanocytes can be reprogrammed into mesenchymal-like cells through a process similar ...
"Melanoma" refers to malignant neoplasm originating from melanocytes. "Prostate cancer" refers to cellular-proliferative ...
Adnexal Neoplasms.- Malignant Adnexal Neoplasms.- Merkel Cell Carcinoma.- Sebaceous Tumors.- Pagets Disease.- Melanocyte ... diagnosis and distinction of rare and/or deadly neoplasms. * a troubleshooting guide dealing with quality control of the frozen ... the discrimination of benign epidermal-derived or adnexal-derived neoplasms. * ... and discrimination of common and problematic cutaneous neoplasms.. Highlights of the Atlas include:. * microscopic anatomy of ...
pigment produced by melanocytes that determines skin, hair, and eye color. melanocyte. cell in the epidermis that produces ... neoplasm. abnormal tissue growth. nevus. birthmark. nodule. small knob of tissue. onychia, onychitis. inflammation of the nail ... virulent skin cancer originating in the melanocytes, usually caused by overexposure to the sun. ...
Histologically, increased numbers of melanocytes and dermal melanophages are present. Melanin deposition in the basal and ... Benign Neoplasms of the Vulva. Douglas V. Horbelt, MD. Division of Gynecologic Oncology, Department of Obstetrics and ... These asymptomatic, slowly growing benign neoplasms arise from neural tissue, and may occur in a deep or superficial location ... Wilkinson EJ: Normal histology and nomenclature of the vulva, and malignant neoplasms, including VIN. Dermatol Clin 10: 283, ...
Tumors of the iris characterized by increased pigmentation of melanocytes. Iris nevi are composed of proliferated melanocytes ... Neoplasms: 649836*Neoplasms by Site: 1*Eye Neoplasms: 42*Uveal Neoplasms*Iris Neoplasms ... Subscribe to New Research on Iris Neoplasms Tumors of the iris characterized by increased pigmentation of melanocytes. Iris ... nevi are composed of proliferated melanocytes and are associated with neurofibromatosis and malignant melanoma of the choroid ...
Chordomas are malignant neoplasms that typically arise in the axial spine and primarily affect adults. When chordomas arise in ... We present an unusual case of gliosarcoma containing numerous islands of well-differentiated melanocytes in a 65 year-old man. ... The CD56+, CD34+, CD33+, MPO-, cytoplasmic CD3+, CD45-, CD7-, HLA-DR-, and TdT- immunophenotype of this neoplasm overlaps with ... We recently observed two cases of solitary subcutaneous neoplasm of the foot with histologic features of spindle cell lipoma ...
Melanoma is a neoplasm derived from melanocytes normally present in the skin specifically in the epidermis. One of the ...
In lentigo maligna, both normal and malignant melanocytes are confined to the epidermis; when malignant melanocytes invade the ... This neoplasm may spread rapidly, causing death within months of its recognition, yet the 5-yr cure rate of early, very ... Histologically, atypical melanocytes characteristically invade dermis and epidermis.. Nodular melanoma constitutes 10 to 15% of ... Moles are circumscribed pigmented macules, papules, or nodules composed of clusters of melanocytes or nevus cells. They may be ...
Spitz nevi are benign melanocytic neoplasms characterized by epithelioid or spindle melanocytes or both. Atypical spitz tumors ... The histology of cases in the single center were primarily solid pseudopapillary neoplasms and endocrine pancreatic neoplasms. ... Solid-pseudopapillary neoplasm of the pancreas in children: Can we predict malignancy?. Hwang J, Kim DY, Kim SC, Namgoong JM, ... Spitzoid neoplasms usually affect young patients (, 20 years old), are typically solitary lesions, and most often occur on the ...
  • SLUG increase occurred concomitantly with SPARC-mediated downregulation of E-cadherin and P-cadherin, and induction of mesenchymal traits in human melanocytes and melanoma cells. (nih.gov)
  • In contrast to the fate of melanoma cells, human melanocytes transplanted into zebrafish embryos most frequently become distributed to their normal microenvironment of the skin, revealing that the zebrafish embryo contains possible homing cues that can be interpreted by normal human cells. (zfin.org)
  • In tests using mouse and human melanocytes, experts found UV radiation from sunlight causes enzymes in the cells to create two chemicals that react together. (amazonaws.com)
  • now show that estrogen increases pigment production in human melanocytes, and progesterone decreases it. (elifesciences.org)
  • Methods In a masked fashion, the serum of two patients with BDUMP was evaluated for the presence of cultured melanocyte elongation and proliferation (CMEP) factor using cultured human melanocytes. (bmj.com)
  • Results The serum of the first case patient was investigated after plasmapheresis and did not demonstrate proliferation of cultured human melanocytes. (bmj.com)
  • A term describing stage of disease for a malignant neoplasm that has spread to parts of the body remote from the primary tumor either by direct extension (beyond immediately adjacent organs or tissues) or by discontinuous metastasis (e.g., implantation or seeding) to distant organs, tissues, or via the lymphatic system to distant lymph nodes. (in.gov)
  • It does not stain normal or tumor tissues from non-melanocyte lineages. (lalpathlabs.com)
  • This case additionally shows marked desmoplasia and irregularly configured nests of melanocytes in the dermis. (nih.gov)
  • El Hamartoma Melanocítico Dérmico es una displasia névica, caracterizada por la ubicación ectópica de melanocitos en dermis , en forma extensiva en napa y persistente. (bvsalud.org)
  • Recent evidence supports a role for SLUG, a transcriptional repressor of E-cadherin, as a melanocyte lineage transcription factor that predisposes to melanoma metastasis. (nih.gov)
  • Here, using dimethylbenzanthracene (DMBA) plus 12-o-tetradecanoyl phorbol-13-acetate (TPA) treatment developing sebaceous neoplasms (SNs) were identified with H&E and Oil red O staining. (medsci.org)
  • We found hair follicle and epidermal cell markers were expressed in sebaceous neoplasms. (medsci.org)
  • Collectively, our findings suggest that the abnormal activation of both HFSCs and Wnt10b/β-catenin signaling involves in the development of sebaceous neoplasms. (medsci.org)
  • However, it remains unknown whether the renewal of sebaceous neoplasms (SNs) induced by TPA is dependent on HFSCs. (medsci.org)
  • The neoplastic melanocytes spread radially along the basement membrane for a very long time before becoming invasive, that s where the name superficial spreading comes from. (healthdocbox.com)
  • The finding of frequent numerical chromosomal aberrations in atypical nodular proliferations arising in CMN identifies these as clonal neoplasms with a genomic instability consistent with a mitotic spindle checkpoint defect. (nih.gov)
  • al12, the biological behavior of melanoma may be related to the expression of the proteins Rb, pRb2/ Treatment p130, p53 and p16, which may be helpful in predicting Notani et al 19 suggests a combination of radical surgery the manifestation of this neoplasm, including the with ample margins and adjuvant chemotherapy as an melanin content. (who.int)
  • Several chapters focus on the posttranscriptional modification of the proteins at the melanocyte cell surface, their role in tumorigenesis, and their potential as therapeutic targets. (doabooks.org)
  • A term describing the behavior of a neoplasm which has all the characteristics of malignancy except invasion of neighboring tissues. (in.gov)