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)

Experimentally induced tumor that produces MELANIN in animals to provide a model for studying human MELANOMA.

Tumors or cancer of the SKIN.

Tumors or cancer of the UVEA.

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)

A melanosome-associated protein that plays a role in the maturation of the MELANOSOME.

Tumors of the choroid; most common intraocular tumors are malignant melanomas of the choroid. These usually occur after puberty and increase in incidence with advancing age. Most malignant melanomas of the uveal tract develop from benign melanomas (nevi).

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.

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.

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.

A raf kinase subclass found at high levels in neuronal tissue. The B-raf Kinases are MAP kinase kinase kinases that have specificity for MAP KINASE KINASE 1 and MAP KINASE KINASE 2.

Cellular antigens that are specific for MELANOMA cells.

A cell line derived from cultured tumor cells.

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.

Clinically atypical nevi (usually exceeding 5 mm in diameter and having variable pigmentation and ill defined borders) with an increased risk for development of non-familial cutaneous malignant melanoma. Biopsies show melanocytic dysplasia. Nevi are clinically and histologically identical to the precursor lesions for melanoma in the B-K mole syndrome. (Stedman, 25th ed)

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.

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.

The transfer of a neoplasm from one organ or part of the body to another remote from the primary site.

Tumors or cancer of the EYE.

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.

A noninvasive technique that enables direct microscopic examination of the surface and architecture of the SKIN.

Experimental transplantation of neoplasms in laboratory animals for research purposes.

Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in neoplastic tissue.

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.

Irradiation directly from the sun.

The surgical removal of the eyeball leaving the eye muscles and remaining orbital contents intact.

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.

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 and ciliary body. Malignant melanoma of the iris often originates from preexisting nevi.

A cellular subtype of malignant melanoma. It is a pigmented lesion composed of melanocytes occurring on sun-exposed skin, usually the face and neck. The melanocytes are commonly multinucleated with a "starburst" appearance. It is considered by many to be the in situ phase of lentigo maligna melanoma.

An antineoplastic agent. It has significant activity against melanomas. (from Martindale, The Extra Pharmacopoeia, 31st ed, p564)

Vaccines or candidate vaccines designed to prevent or treat cancer. Vaccines are produced using the patient's own whole tumor cells as the source of antigens, or using tumor-specific antigens, often recombinantly produced.

Substances that inhibit or prevent the proliferation of NEOPLASMS.

Ability of neoplasms to infiltrate and actively destroy surrounding tissue.

Disorders of increased melanin pigmentation that develop without preceding inflammatory disease.

Mutant mice homozygous for the recessive gene "nude" which fail to develop a thymus. They are useful in tumor studies and studies on immune responses.

Coloration of the skin.

Lymphocytes that show specificity for autologous tumor cells. Ex vivo isolation and culturing of TIL with interleukin-2, followed by reinfusion into the patient, is one form of adoptive immunotherapy of cancer.

Histochemical localization of immunoreactive substances using labeled antibodies as reagents.

A diagnostic procedure used to determine whether LYMPHATIC METASTASIS has occurred. The sentinel lymph node is the first lymph node to receive drainage from a neoplasm.

One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.

Transfer of a neoplasm from its primary site to lymph nodes or to distant parts of the body by way of the lymphatic system.

Manipulation of the host's immune system in treatment of disease. It includes both active and passive immunization as well as immunosuppressive therapy to prevent graft rejection.

A benign compound nevus occurring most often in children before puberty, composed of spindle and epithelioid cells located mainly in the dermis, sometimes in association with large atypical cells and multinucleate cells, and having a close histopathological resemblance to malignant melanoma. The tumor presents as a smooth to slightly scaly, round to oval, raised, firm papule or nodule, ranging in color from pink-tan to purplish red, often with surface telangiectasia. (Dorland, 27th ed)

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.

Tumors or cancer of the CONJUNCTIVA.

All of the processes involved in increasing CELL NUMBER including CELL DIVISION.

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.

A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations.

Color of hair or fur.

Methods which attempt to express in replicable terms the extent of the neoplasm in the patient.

Transplantation between animals of different species.

An order of fish with eight families and numerous species of both egg-laying and livebearing fish. Families include Cyprinodontidae (egg-laying KILLIFISHES;), FUNDULIDAEl; (topminnows), Goodeidae (Mexican livebearers), Jenynsiidae (jenynsiids), Poeciliidae (livebearers), Profundulidae (Middle American killifishes), Aplocheilidae, and Rivulidae (rivulines). In the family Poeciliidae, the guppy and molly belong to the genus POECILIA.

The worsening of a disease over time. This concept is most often used for chronic and incurable diseases where the stage of the disease is an important determinant of therapy and prognosis.

An injury to the skin causing erythema, tenderness, and sometimes blistering and resulting from excessive exposure to the sun. The reaction is produced by the ultraviolet radiation in sunlight.

A cell adhesion molecule of the immunoglobulin superfamily that is expressed in ENDOTHELIAL CELLS and is involved in INTERCELLULAR JUNCTIONS.

Antibodies produced by a single clone of cells.

The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.

A family of highly acidic calcium-binding proteins found in large concentration in the brain and believed to be glial in origin. They are also found in other organs in the body. They have in common the EF-hand motif (EF HAND MOTIFS) found on a number of calcium binding proteins. The name of this family derives from the property of being soluble in a 100% saturated ammonium sulfate solution.

A specific HLA-A surface antigen subtype. Members of this subtype contain alpha chains that are encoded by the HLA-A*02 allele family.

The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.

A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.

Immunoglobulins induced by antigens specific for tumors other than the normally occurring HISTOCOMPATIBILITY ANTIGENS.

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.

Tumors or cancer of the LUNG.

Tumor suppressor genes located on human chromosome 9 in the region 9p21. This gene is either deleted or mutated in a wide range of malignancies. (From Segen, Current Med Talk, 1995) Two alternatively spliced gene products are encoded by p16: CYCLIN-DEPENDENT KINASE INHIBITOR P16 and TUMOR SUPPRESSOR PROTEIN P14ARF.

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.

The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.

The inspection of one's own body, usually for signs of disease (e.g., BREAST SELF-EXAMINATION, testicular self-examination).

The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.

RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.

Adherence of cells to surfaces or to other cells.

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.

The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.

Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.

Found in large amounts in the plasma and urine of patients with malignant melanoma. It is therefore used in the diagnosis of melanoma and for the detection of postoperative metastases. Cysteinyldopa is believed to be formed by the rapid enzymatic hydrolysis of 5-S-glutathionedopa found in melanin-producing cells.

Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.

A product of the p16 tumor suppressor gene (GENES, P16). It is also called INK4 or INK4A because it is the prototype member of the INK4 CYCLIN-DEPENDENT KINASE INHIBITORS. This protein is produced from the alpha mRNA transcript of the p16 gene. The other gene product, produced from the alternatively spliced beta transcript, is TUMOR SUPPRESSOR PROTEIN P14ARF. Both p16 gene products have tumor suppressor functions.

DNA present in neoplastic tissue.

Coloration or discoloration of a part by a pigment.

A pathologic process consisting of the proliferation of blood vessels in abnormal tissues or in abnormal positions.

A subclass of ACIDIC GLYCOSPHINGOLIPIDS. They contain one or more sialic acid (N-ACETYLNEURAMINIC ACID) residues. Using the Svennerholm system of abbrevations, gangliosides are designated G for ganglioside, plus subscript M, D, or T for mono-, di-, or trisialo, respectively, the subscript letter being followed by a subscript arabic numeral to indicated sequence of migration in thin-layer chromatograms. (From Oxford Dictionary of Biochemistry and Molecular Biology, 1997)

The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.

Form of adoptive transfer where cells with antitumor activity are transferred to the tumor-bearing host in order to mediate tumor regression. The lymphoid cells commonly used are lymphokine-activated killer (LAK) cells and tumor-infiltrating lymphocytes (TIL). This is usually considered a form of passive immunotherapy. (From DeVita, et al., Cancer, 1993, pp.305-7, 314)

Immunized T-lymphocytes which can directly destroy appropriate target cells. These cytotoxic lymphocytes may be generated in vitro in mixed lymphocyte cultures (MLC), in vivo during a graft-versus-host (GVH) reaction, or after immunization with an allograft, tumor cell or virally transformed or chemically modified target cell. The lytic phenomenon is sometimes referred to as cell-mediated lympholysis (CML). These CD8-positive cells are distinct from NATURAL KILLER CELLS and NATURAL KILLER T-CELLS. There are two effector phenotypes: TC1 and TC2.

Established cell cultures that have the potential to propagate indefinitely.

Small double-stranded, non-protein coding RNAs (21-31 nucleotides) involved in GENE SILENCING functions, especially RNA INTERFERENCE (RNAi). Endogenously, siRNAs are generated from dsRNAs (RNA, DOUBLE-STRANDED) by the same ribonuclease, Dicer, that generates miRNAs (MICRORNAS). The perfect match of the siRNAs' antisense strand to their target RNAs mediates RNAi by siRNA-guided RNA cleavage. siRNAs fall into different classes including trans-acting siRNA (tasiRNA), repeat-associated RNA (rasiRNA), small-scan RNA (scnRNA), and Piwi protein-interacting RNA (piRNA) and have different specific gene silencing functions.

In vivo methods of screening investigative anticancer drugs, biologic response modifiers or radiotherapies. Human tumor tissue or cells are transplanted into mice or rats followed by tumor treatment regimens. A variety of outcomes are monitored to assess antitumor effectiveness.

Small circumscribed melanoses resembling, but differing histologically from, freckles. The concept includes senile lentigo ('liver spots') and nevoid lentigo (nevus spilus, lentigo simplex) and may also occur in association with multiple congenital defects or congenital syndromes (e.g., Peutz-Jeghers syndrome).

They are oval or bean shaped bodies (1 - 30 mm in diameter) located along the lymphatic system.

Glycoproteins found on the membrane or surface of cells.

Mice homozygous for the mutant autosomal recessive gene "scid" which is located on the centromeric end of chromosome 16. These mice lack mature, functional lymphocytes and are thus highly susceptible to lethal opportunistic infections if not chronically treated with antibiotics. The lack of B- and T-cell immunity resembles severe combined immunodeficiency (SCID) syndrome in human infants. SCID mice are useful as animal models since they are receptive to implantation of a human immune system producing SCID-human (SCID-hu) hematochimeric mice.

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.

One of the type I interferons produced by peripheral blood leukocytes or lymphoblastoid cells. In addition to antiviral activity, it activates NATURAL KILLER CELLS and B-LYMPHOCYTES, and down-regulates VASCULAR ENDOTHELIAL GROWTH FACTOR expression through PI-3 KINASE and MAPK KINASES signaling pathways.

Exfoliate neoplastic cells circulating in the blood and associated with metastasizing tumors.

The phenomenon of target cell destruction by immunologically active effector cells. It may be brought about directly by sensitized T-lymphocytes or by lymphoid or myeloid "killer" cells, or it may be mediated by cytotoxic antibody, cytotoxic factor released by lymphoid cells, or complement.

Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.

A negative regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.

Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.

A soluble substance elaborated by antigen- or mitogen-stimulated T-LYMPHOCYTES which induces DNA synthesis in naive lymphocytes.

A class of statistical procedures for estimating the survival function (function of time, starting with a population 100% well at a given time and providing the percentage of the population still well at later times). The survival analysis is then used for making inferences about the effects of treatments, prognostic factors, exposures, and other covariates on the function.

Active immunization where vaccine is administered for therapeutic or preventive purposes. This can include administration of immunopotentiating agents such as BCG vaccine and Corynebacterium parvum as well as biological response modifiers such as interferons, interleukins, and colony-stimulating factors in order to directly stimulate the immune system.

Surgical excision of one or more lymph nodes. Its most common use is in cancer surgery. (From Dorland, 28th ed, p966)

Color of the iris.

The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.

Elements of limited time intervals, contributing to particular results or situations.

A group of compounds that contain the structure SO2NH2.

Resistance or diminished response of a neoplasm to an antineoplastic agent in humans, animals, or cell or tissue cultures.

The proportion of survivors in a group, e.g., of patients, studied and followed over a period, or the proportion of persons in a specified group alive at the beginning of a time interval who survive to the end of the interval. It is often studied using life table methods.

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.

A positive regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.

Immunologic techniques based on the use of: (1) enzyme-antibody conjugates; (2) enzyme-antigen conjugates; (3) antienzyme antibody followed by its homologous enzyme; or (4) enzyme-antienzyme complexes. These are used histologically for visualizing or labeling tissue specimens.

Methods of investigating the effectiveness of anticancer cytotoxic drugs and biologic inhibitors. These include in vitro cell-kill models and cytostatic dye exclusion tests as well as in vivo measurement of tumor growth parameters in laboratory animals.

RNA present in neoplastic tissue.

The determination of the pattern of genes expressed at the level of GENETIC TRANSCRIPTION, under specific circumstances or in a specific cell.

A class of drugs that differs from other alkylating agents used clinically in that they are monofunctional and thus unable to cross-link cellular macromolecules. Among their common properties are a requirement for metabolic activation to intermediates with antitumor efficacy and the presence in their chemical structures of N-methyl groups, that after metabolism, can covalently modify cellular DNA. The precise mechanisms by which each of these drugs acts to kill tumor cells are not completely understood. (From AMA, Drug Evaluations Annual, 1994, p2026)

Exposing oneself to SUNLIGHT or ULTRAVIOLET RAYS.

Family of retrovirus-associated DNA sequences (ras) originally isolated from Harvey (H-ras, Ha-ras, rasH) and Kirsten (K-ras, Ki-ras, rasK) murine sarcoma viruses. Ras genes are widely conserved among animal species and sequences corresponding to both H-ras and K-ras genes have been detected in human, avian, murine, and non-vertebrate genomes. The closely related N-ras gene has been detected in human neuroblastoma and sarcoma cell lines. All genes of the family have a similar exon-intron structure and each encodes a p21 protein.

Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.

A group of genetically identical cells all descended from a single common ancestral cell by mitosis in eukaryotes or by binary fission in prokaryotes. Clone cells also include populations of recombinant DNA molecules all carrying the same inserted sequence. (From King & Stansfield, Dictionary of Genetics, 4th ed)

Benzopyrroles with the nitrogen at the number one carbon adjacent to the benzyl portion, in contrast to ISOINDOLES which have the nitrogen away from the six-membered ring.

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.

Differentiation antigens residing on mammalian leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similar reactivity with certain subpopulations of antigens of a particular lineage or differentiation stage. The subpopulations of antigens are also known by the same CD designation.

In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.

Proteins prepared by recombinant DNA technology.

Neoplasm drug therapy involving an extracorporeal circuit with temporary exclusion of the tumor-bearing area from the general circulation during which high concentrations of the drug are perfused to the isolated part.

Unstable isotopes of ruthenium that decay or disintegrate emitting radiation. Ru atoms with atomic weights 93-95, 97, 103, and 105-108 are radioactive ruthenium isotopes.

Disappearance of a neoplasm or neoplastic state without the intervention of therapy.

A critical subpopulation of regulatory T-lymphocytes involved in MHC Class I-restricted interactions. They include both cytotoxic T-lymphocytes (T-LYMPHOCYTES, CYTOTOXIC) and CD8+ suppressor T-lymphocytes.

The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.

The total amount (cell number, weight, size or volume) of tumor cells or tissue in the body.

Polymorphic class I human histocompatibility (HLA) surface antigens present on almost all nucleated cells. At least 20 antigens have been identified which are encoded by the A locus of multiple alleles on chromosome 6. They serve as targets for T-cell cytolytic responses and are involved with acceptance or rejection of tissue/organ grafts.

Tumors, cancer or other neoplasms produced by exposure to ionizing or non-ionizing radiation.

Neoplasms of the intracranial components of the central nervous system, including the cerebral hemispheres, basal ganglia, hypothalamus, thalamus, brain stem, and cerebellum. Brain neoplasms are subdivided into primary (originating from brain tissue) and secondary (i.e., metastatic) forms. Primary neoplasms are subdivided into benign and malignant forms. In general, brain tumors may also be classified by age of onset, histologic type, or presenting location in the brain.

The local recurrence of a neoplasm following treatment. It arises from microscopic cells of the original neoplasm that have escaped therapeutic intervention and later become clinically visible at the original site.

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.

Removal and pathologic examination of specimens in the form of small pieces of tissue from the living body.

Period after successful treatment in which there is no appearance of the symptoms or effects of the disease.

A specific pair of GROUP C CHROMSOMES of the human chromosome classification.

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)

The condition in which one chromosome of a pair is missing. In a normally diploid cell it is represented symbolically as 2N-1.

A specific HLA-A surface antigen subtype. Members of this subtype contain alpha chains that are encoded by the HLA-A*01 allele family.

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.

Benign eccrine poromas that present as multiple oval, brown-to-black plaques, located mostly on the chest and back. The age of onset is usually in the fourth or fifth decade.

A malignant skin neoplasm that seldom metastasizes but has potentialities for local invasion and destruction. Clinically it is divided into types: nodular, cicatricial, morphaic, and erythematoid (pagetoid). They develop on hair-bearing skin, most commonly on sun-exposed areas. Approximately 85% are found on the head and neck area and the remaining 15% on the trunk and limbs. (From DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1471)

Biochemical identification of mutational changes in a nucleotide sequence.

Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.

Hybridization of a nucleic acid sample to a very large set of OLIGONUCLEOTIDE PROBES, which have been attached individually in columns and rows to a solid support, to determine a BASE SEQUENCE, or to detect variations in a gene sequence, GENE EXPRESSION, or for GENE MAPPING.

Chemical or physical agents that protect the skin from sunburn and erythema by absorbing or blocking ultraviolet radiation.

The artificial induction of GENE SILENCING by the use of RNA INTERFERENCE to reduce the expression of a specific gene. It includes the use of DOUBLE-STRANDED RNA, such as SMALL INTERFERING RNA and RNA containing HAIRPIN LOOP SEQUENCE, and ANTI-SENSE OLIGONUCLEOTIDES.

Cell changes manifested by escape from control mechanisms, increased growth potential, alterations in the cell surface, karyotypic abnormalities, morphological and biochemical deviations from the norm, and other attributes conferring the ability to invade, metastasize, and kill.

The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from PREVALENCE, which refers to all cases, new or old, in the population at a given time.

Radionuclide imaging of the LYMPHATIC SYSTEM.

The relationship between the dose of an administered drug and the response of the organism to the drug.

A calcium-binding protein that is 92 AA long, contains 2 EF-hand domains, and is concentrated mainly in GLIAL CELLS. Elevation of S100B levels in brain tissue correlates with a role in neurological disorders.

An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.

The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.

The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.

Specialized cells of the hematopoietic system that have branch-like extensions. They are found throughout the lymphatic system, and in non-lymphoid tissues such as SKIN and the epithelia of the intestinal, respiratory, and reproductive tracts. They trap and process ANTIGENS, and present them to T-CELLS, thereby stimulating CELL-MEDIATED IMMUNITY. They are different from the non-hematopoietic FOLLICULAR DENDRITIC CELLS, which have a similar morphology and immune system function, but with respect to humoral immunity (ANTIBODY PRODUCTION).

Membrane proteins encoded by the BCL-2 GENES and serving as potent inhibitors of cell death by APOPTOSIS. The proteins are found on mitochondrial, microsomal, and NUCLEAR MEMBRANE sites within many cell types. Overexpression of bcl-2 proteins, due to a translocation of the gene, is associated with follicular lymphoma.

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.

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.

The major interferon produced by mitogenically or antigenically stimulated LYMPHOCYTES. It is structurally different from TYPE I INTERFERON and its major activity is immunoregulation. It has been implicated in the expression of CLASS II HISTOCOMPATIBILITY ANTIGENS in cells that do not normally produce them, leading to AUTOIMMUNE DISEASES.

Bone marrow-derived lymphocytes that possess cytotoxic properties, classically directed against transformed and virus-infected cells. Unlike T CELLS; and B CELLS; NK CELLS are not antigen specific. The cytotoxicity of natural killer cells is determined by the collective signaling of an array of inhibitory and stimulatory CELL SURFACE RECEPTORS. A subset of T-LYMPHOCYTES referred to as NATURAL KILLER T CELLS shares some of the properties of this cell type.

Melanin-containing organelles found in melanocytes and melanophores.

An intracellular signaling system involving the MAP kinase cascades (three-membered protein kinase cascades). Various upstream activators, which act in response to extracellular stimuli, trigger the cascades by activating the first member of a cascade, MAP KINASE KINASE KINASES; (MAPKKKs). Activated MAPKKKs phosphorylate MITOGEN-ACTIVATED PROTEIN KINASE KINASES which in turn phosphorylate the MITOGEN-ACTIVATED PROTEIN KINASES; (MAPKs). The MAPKs then act on various downstream targets to affect gene expression. In mammals, there are several distinct MAP kinase pathways including the ERK (extracellular signal-regulated kinase) pathway, the SAPK/JNK (stress-activated protein kinase/c-jun kinase) pathway, and the p38 kinase pathway. There is some sharing of components among the pathways depending on which stimulus originates activation of the cascade.

Processes required for CELL ENLARGEMENT and CELL PROLIFERATION.

The simultaneous analysis of multiple samples of TISSUES or CELLS from BIOPSY or in vitro culture that have been arranged in an array format on slides or microchips.

Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)

Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.

The ability of tumors to evade destruction by the IMMUNE SYSTEM. Theories concerning possible mechanisms by which this takes place involve both cellular immunity (IMMUNITY, CELLULAR) and humoral immunity (ANTIBODY FORMATION), and also costimulatory pathways related to CD28 antigens (ANTIGENS, CD28) and CD80 antigens (ANTIGENS, CD80).

Diseases of the nail plate and tissues surrounding it. The concept is limited to primates.

Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.