Tumor Burden
Cell Line, Tumor
A cell line derived from cultured tumor cells.
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 Necrosis Factor-alpha
Serum glycoprotein produced by activated MACROPHAGES and other mammalian MONONUCLEAR LEUKOCYTES. It has necrotizing activity against tumor cell lines and increases ability to reject tumor transplants. Also known as TNF-alpha, it is only 30% homologous to TNF-beta (LYMPHOTOXIN), but they share TNF RECEPTORS.
Neoplasms, Experimental
Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.
Mammary Neoplasms, Experimental
Experimentally induced mammary neoplasms in animals to provide a model for studying human BREAST NEOPLASMS.
Xenograft Model Antitumor Assays
Neoplasm Metastasis
Mice, Nude
Wilms Tumor
A malignant kidney tumor, caused by the uncontrolled multiplication of renal stem (blastemal), stromal (STROMAL CELLS), and epithelial (EPITHELIAL CELLS) elements. However, not all three are present in every case. Several genes or chromosomal areas have been associated with Wilms tumor which is usually found in childhood as a firm lump in a child's side or ABDOMEN.
Neuroendocrine Tumors
Tumors whose cells possess secretory granules and originate from the neuroectoderm, i.e., the cells of the ectoblast or epiblast that program the neuroendocrine system. Common properties across most neuroendocrine tumors include ectopic hormone production (often via APUD CELLS), the presence of tumor-associated antigens, and isozyme composition.
Neovascularization, Pathologic
Tumor Suppressor Protein p53
Nuclear phosphoprotein encoded by the p53 gene (GENES, P53) whose normal function is to control CELL PROLIFERATION and APOPTOSIS. A mutant or absent p53 protein has been found in LEUKEMIA; OSTEOSARCOMA; LUNG CANCER; and COLORECTAL CANCER.
Genes, Tumor Suppressor
Genes that inhibit expression of the tumorigenic phenotype. They are normally involved in holding cellular growth in check. When tumor suppressor genes are inactivated or lost, a barrier to normal proliferation is removed and unregulated growth is possible.
Brain Neoplasms
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.
Tumor Microenvironment
The milieu surrounding neoplasms consisting of cells, vessels, soluble factors, and molecules, that can influence and be influenced by, the neoplasm's growth.
Mice, Inbred BALB C
Cell Proliferation
All of the processes involved in increasing CELL NUMBER including CELL DIVISION.
Neoplasm Transplantation
Experimental transplantation of neoplasms in laboratory animals for research purposes.
Carcinoid Tumor
A usually small, slow-growing neoplasm composed of islands of rounded, oxyphilic, or spindle-shaped cells of medium size, with moderately small vesicular nuclei, and covered by intact mucosa with a yellow cut surface. The tumor can occur anywhere in the gastrointestinal tract (and in the lungs and other sites); approximately 90% arise in the appendix. It is now established that these tumors are of neuroendocrine origin and derive from a primitive stem cell. (From Stedman, 25th ed & Holland et al., Cancer Medicine, 3d ed, p1182)
Mice, Inbred C57BL
Inbred C57BL mice are a strain of laboratory mice that have been produced by many generations of brother-sister matings, resulting in a high degree of genetic uniformity and homozygosity, making them widely used for biomedical research, including studies on genetics, immunology, cancer, and neuroscience.
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.
Mice, SCID
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.
Neoplasms
Disease Models, Animal
Disease Progression
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.
Tumor Suppressor Proteins
Antigens, Neoplasm
Neoplasm Staging
Treatment Outcome
Cost of Illness
The personal cost of acute or chronic disease. The cost to the patient may be an economic, social, or psychological cost or personal loss to self, family, or immediate community. The cost of illness may be reflected in absenteeism, productivity, response to treatment, peace of mind, or QUALITY OF LIFE. It differs from HEALTH CARE COSTS, meaning the societal cost of providing services related to the delivery of health care, rather than personal impact on individuals.
Antineoplastic Agents
Substances that inhibit or prevent the proliferation of NEOPLASMS.
Mice, Transgenic
Melanoma, Experimental
Experimentally induced tumor that produces MELANIN in animals to provide a model for studying human MELANOMA.
Cell Division
Fibrosarcoma
Body Burden
Cell Transformation, Neoplastic
Neoplasm 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.
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).
Sarcoma, Experimental
Experimentally induced neoplasms of CONNECTIVE TISSUE in animals to provide a model for studying human SARCOMA.
Immunotherapy
Survival Analysis
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.
Combined Modality Therapy
The treatment of a disease or condition by several different means simultaneously or sequentially. Chemoimmunotherapy, RADIOIMMUNOTHERAPY, chemoradiotherapy, cryochemotherapy, and SALVAGE THERAPY are seen most frequently, but their combinations with each other and surgery are also used.
RNA, Messenger
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.
Cancer Vaccines
Gastrointestinal Stromal Tumors
Signal Transduction
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.
Lymphatic Metastasis
Transfer of a neoplasm from its primary site to lymph nodes or to distant parts of the body by way of the lymphatic system.
Reverse Transcriptase Polymerase Chain Reaction
Neoplasm Recurrence, Local
Antineoplastic Combined Chemotherapy Protocols
The use of two or more chemicals simultaneously or sequentially in the drug therapy of neoplasms. The drugs need not be in the same dosage form.
Prognosis
Glioma
Benign and malignant central nervous system neoplasms derived from glial cells (i.e., astrocytes, oligodendrocytes, and ependymocytes). Astrocytes may give rise to astrocytomas (ASTROCYTOMA) or glioblastoma multiforme (see GLIOBLASTOMA). Oligodendrocytes give rise to oligodendrogliomas (OLIGODENDROGLIOMA) and ependymocytes may undergo transformation to become EPENDYMOMA; CHOROID PLEXUS NEOPLASMS; or colloid cysts of the third ventricle. (From Escourolle et al., Manual of Basic Neuropathology, 2nd ed, p21)
Retrospective Studies
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.
Immunohistochemistry
Genetic Therapy
Apoptosis
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.
Survival Rate
Gene Expression Regulation, Neoplastic
9,10-Dimethyl-1,2-benzanthracene
Carcinoma, Squamous Cell
Carcinoma 256, Walker
Carcinogens
Glioblastoma
A malignant form of astrocytoma histologically characterized by pleomorphism of cells, nuclear atypia, microhemorrhage, and necrosis. They may arise in any region of the central nervous system, with a predilection for the cerebral hemispheres, basal ganglia, and commissural pathways. Clinical presentation most frequently occurs in the fifth or sixth decade of life with focal neurologic signs or seizures.
Angiogenesis Inhibitors
Carcinoma, Ehrlich Tumor
Flow Cytometry
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.
Carcinoma, Hepatocellular
A primary malignant neoplasm of epithelial liver cells. It ranges from a well-differentiated tumor with EPITHELIAL CELLS indistinguishable from normal HEPATOCYTES to a poorly differentiated neoplasm. The cells may be uniform or markedly pleomorphic, or form GIANT CELLS. Several classification schemes have been suggested.
Cell Survival
Blotting, Western
Immunotherapy, Adoptive
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)
Tomography, X-Ray Computed
Multiple Myeloma
A malignancy of mature PLASMA CELLS engaging in monoclonal immunoglobulin production. It is characterized by hyperglobulinemia, excess Bence-Jones proteins (free monoclonal IMMUNOGLOBULIN LIGHT CHAINS) in the urine, skeletal destruction, bone pain, and fractures. Other features include ANEMIA; HYPERCALCEMIA; and RENAL INSUFFICIENCY.
Retinoblastoma
A malignant tumor arising from the nuclear layer of the retina that is the most common primary tumor of the eye in children. The tumor tends to occur in early childhood or infancy and may be present at birth. The majority are sporadic, but the condition may be transmitted as an autosomal dominant trait. Histologic features include dense cellularity, small round polygonal cells, and areas of calcification and necrosis. An abnormal pupil reflex (leukokoria); NYSTAGMUS, PATHOLOGIC; STRABISMUS; and visual loss represent common clinical characteristics of this condition. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2104)
Immunoenzyme Techniques
Mutation
Ardisia
Doxorubicin
Dose-Response Relationship, Drug
Neoplastic Cells, Circulating
Cell Growth Processes
Processes required for CELL ENLARGEMENT and CELL PROLIFERATION.
Lymph Nodes
Mice, Knockout
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
Cell Movement
Disease-Free Survival
Papilloma
Rhabdoid Tumor
A rare but highly lethal childhood tumor found almost exclusively in infants. Histopathologically, it resembles RHABDOMYOSARCOMA but the tumor cells are not of myogenic origin. Although it arises primarily in the kidney, it may be found in other parts of the body. The rhabdoid cytomorphology is believed to be the expression of a very primitive malignant cell. (From Holland et al., Cancer Medicine, 3d ed, p2210)
Magnetic Resonance Imaging
Transfection
Positron-Emission Tomography
An imaging technique using compounds labelled with short-lived positron-emitting radionuclides (such as carbon-11, nitrogen-13, oxygen-15 and fluorine-18) to measure cell metabolism. It has been useful in study of soft tissues such as CANCER; CARDIOVASCULAR SYSTEM; and brain. SINGLE-PHOTON EMISSION-COMPUTED TOMOGRAPHY is closely related to positron emission tomography, but uses isotopes with longer half-lives and resolution is lower.
Polymerase Chain Reaction
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.
Cyclophosphamide
Precursor of an alkylating nitrogen mustard antineoplastic and immunosuppressive agent that must be activated in the LIVER to form the active aldophosphamide. It has been used in the treatment of LYMPHOMA and LEUKEMIA. Its side effect, ALOPECIA, has been used for defleecing sheep. Cyclophosphamide may also cause sterility, birth defects, mutations, and cancer.
Carcinoma, Renal Cell
Granulosa Cell Tumor
A neoplasm composed entirely of GRANULOSA CELLS, occurring mostly in the OVARY. In the adult form, it may contain some THECA CELLS. This tumor often produces ESTRADIOL and INHIBIN. The excess estrogen exposure can lead to other malignancies in women and PRECOCIOUS PUBERTY in girls. In rare cases, granulosa cell tumors have been identified in the TESTES.
Neuroblastoma
A common neoplasm of early childhood arising from neural crest cells in the sympathetic nervous system, and characterized by diverse clinical behavior, ranging from spontaneous remission to rapid metastatic progression and death. This tumor is the most common intraabdominal malignancy of childhood, but it may also arise from thorax, neck, or rarely occur in the central nervous system. Histologic features include uniform round cells with hyperchromatic nuclei arranged in nests and separated by fibrovascular septa. Neuroblastomas may be associated with the opsoclonus-myoclonus syndrome. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2099-2101; Curr Opin Oncol 1998 Jan;10(1):43-51)
Adenocarcinoma, Bronchiolo-Alveolar
A carcinoma thought to be derived from epithelium of terminal bronchioles, in which the neoplastic tissue extends along the alveolar walls and grows in small masses within the alveoli. Involvement may be uniformly diffuse and massive, or nodular, or lobular. The neoplastic cells are cuboidal or columnar and form papillary structures. Mucin may be demonstrated in some of the cells and in the material in the alveoli, which also includes denuded cells. Metastases in regional lymph nodes, and in even more distant sites, are known to occur, but are infrequent. (From Stedman, 25th ed)
Follow-Up Studies
Gene Expression Profiling
Tissue Distribution
Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.
Carcinoembryonic Antigen
Rats, Inbred F344
Cells, Cultured
Carcinoma, Lewis Lung
A carcinoma discovered by Dr. Margaret R. Lewis of the Wistar Institute in 1951. This tumor originated spontaneously as a carcinoma of the lung of a C57BL mouse. The tumor does not appear to be grossly hemorrhagic and the majority of the tumor tissue is a semifirm homogeneous mass. (From Cancer Chemother Rep 2 1972 Nov;(3)1:325) It is also called 3LL and LLC and is used as a transplantable malignancy.
Lymphocytes, Tumor-Infiltrating
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.
Radiopharmaceuticals
Adenoviridae
Gene Expression
Sensitivity and Specificity
Osteosarcoma
Cisplatin
An inorganic and water-soluble platinum complex. After undergoing hydrolysis, it reacts with DNA to produce both intra and interstrand crosslinks. These crosslinks appear to impair replication and transcription of DNA. The cytotoxicity of cisplatin correlates with cellular arrest in the G2 phase of the cell cycle.
Base Sequence
Cytotoxicity, Immunologic
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.
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)
Receptors, Tumor Necrosis Factor, Type I
A tumor necrosis factor receptor subtype that has specificity for TUMOR NECROSIS FACTOR ALPHA and LYMPHOTOXIN ALPHA. It is constitutively expressed in most tissues and is a key mediator of tumor necrosis factor signaling in the vast majority of cells. The activated receptor signals via a conserved death domain that associates with specific TNF RECEPTOR-ASSOCIATED FACTORS in the CYTOPLASM.
Down-Regulation
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.
Phyllodes Tumor
A type of connective tissue neoplasm typically arising from intralobular stroma of the breast. It is characterized by the rapid enlargement of an asymmetric firm mobile mass. Histologically, its leaf-like stromal clefts are lined by EPITHELIAL CELLS. Rare phyllodes tumor of the prostate is also known.
Kaplan-Meier Estimate
A nonparametric method of compiling LIFE TABLES or survival tables. It combines calculated probabilities of survival and estimates to allow for observations occurring beyond a measurement threshold, which are assumed to occur randomly. Time intervals are defined as ending each time an event occurs and are therefore unequal. (From Last, A Dictionary of Epidemiology, 1995)
Tumor Stem Cell Assay
A cytologic technique for measuring the functional capacity of tumor stem cells by assaying their activity. It is used primarily for the in vitro testing of antineoplastic agents.
Whole Body Imaging
The creation of a visual display of the inside of the entire body of a human or animal for the purposes of diagnostic evaluation. This is most commonly achieved by using MAGNETIC RESONANCE IMAGING; or POSITRON EMISSION TOMOGRAPHY.
Cytokines
Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.
Radioimmunotherapy
Radiotherapy where cytotoxic radionuclides are linked to antibodies in order to deliver toxins directly to tumor targets. Therapy with targeted radiation rather than antibody-targeted toxins (IMMUNOTOXINS) has the advantage that adjacent tumor cells, which lack the appropriate antigenic determinants, can be destroyed by radiation cross-fire. Radioimmunotherapy is sometimes called targeted radiotherapy, but this latter term can also refer to radionuclides linked to non-immune molecules (see RADIOTHERAPY).
Pyran Copolymer
Copolymer of divinyl ether and maleic anhydride that acts as an immunostimulant with antineoplastic and anti-infective properties. It is used in combination with other antineoplastic agents.
Diphosphonates
Organic compounds which contain P-C-P bonds, where P stands for phosphonates or phosphonic acids. These compounds affect calcium metabolism. They inhibit ectopic calcification and slow down bone resorption and bone turnover. Technetium complexes of diphosphonates have been used successfully as bone scanning agents.
Genes, ras
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.
Genetic Vectors
DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.
Mice, Inbred Strains
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.
Croton Oil
T-Lymphocytes
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.
Cell Cycle
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.
Molecular Sequence Data
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.
Drug Delivery Systems
RNA, Small Interfering
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.
Up-Regulation
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.
Neuroectodermal Tumors, Primitive
A group of malignant tumors of the nervous system that feature primitive cells with elements of neuronal and/or glial differentiation. Use of this term is limited by some authors to central nervous system tumors and others include neoplasms of similar origin which arise extracranially (i.e., NEUROECTODERMAL TUMORS, PRIMITIVE, PERIPHERAL). This term is also occasionally used as a synonym for MEDULLOBLASTOMA. In general, these tumors arise in the first decade of life and tend to be highly malignant. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2059)
Neoplastic Stem Cells
Highly proliferative, self-renewing, and colony-forming stem cells which give rise to NEOPLASMS.
Astrocytoma
Neoplasms of the brain and spinal cord derived from glial cells which vary from histologically benign forms to highly anaplastic and malignant tumors. Fibrillary astrocytomas are the most common type and may be classified in order of increasing malignancy (grades I through IV). In the first two decades of life, astrocytomas tend to originate in the cerebellar hemispheres; in adults, they most frequently arise in the cerebrum and frequently undergo malignant transformation. (From Devita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2013-7; Holland et al., Cancer Medicine, 3d ed, p1082)
Giant Cell Tumor of Bone
A bone tumor composed of cellular spindle-cell stroma containing scattered multinucleated giant cells resembling osteoclasts. The tumors range from benign to frankly malignant lesions. The tumor occurs most frequently in an end of a long tubular bone in young adults. (From Dorland, 27th ed; Stedman, 25th ed)
Glomus Tumor
A blue-red, extremely painful vascular neoplasm involving a glomeriform arteriovenous anastomosis (glomus body), which may be found anywhere in the skin, most often in the distal portion of the fingers and toes, especially beneath the nail. It is composed of specialized pericytes (sometimes termed glomus cells), usually in single encapsulated nodular masses which may be several millimeters in diameter (From Stedman, 27th ed). CHEMODECTOMA, a tumor of NEURAL CREST origin, is also sometimes called a glomus tumor.
Models, Biological
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Oncolytic Viruses
Tumor-selective, replication competent VIRUSES that have antineoplastic effects. This is achieved by producing cytotoxicity-enhancing proteins and/or eliciting an antitumor immune response. They are genetically engineered so that they can replicate in CANCER cells but not in normal cells, and are used in ONCOLYTIC VIROTHERAPY.
Phenotype
Oncolytic Virotherapy
Use of attenuated VIRUSES as ANTINEOPLASTIC AGENTS to selectively kill CANCER cells.
Interferon-gamma
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.
Chromogranin A
A type of chromogranin which was first isolated from CHROMAFFIN CELLS of the ADRENAL MEDULLA but is also found in other tissues and in many species including human, bovine, rat, mouse, and others. It is an acidic protein with 431 to 445 amino acid residues. It contains fragments that inhibit vasoconstriction or release of hormones and neurotransmitter, while other fragments exert antimicrobial actions.
Osteoclasts
Giant Cell Tumors
Tumors of bone tissue or synovial or other soft tissue characterized by the presence of giant cells. The most common are giant cell tumor of tendon sheath and GIANT CELL TUMOR OF BONE.
Neoplasm, Residual
Leydig Cell Tumor
Gonadal interstitial or stromal cell neoplasm composed of only LEYDIG CELLS. These tumors may produce one or more of the steroid hormones such as ANDROGENS; ESTROGENS; and CORTICOSTEROIDS. Clinical symptoms include testicular swelling, GYNECOMASTIA, sexual precocity in children, or virilization (VIRILISM) in females.
CD8-Positive T-Lymphocytes
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.
Risk Factors
Enzyme-Linked Immunosorbent Assay
An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.
Genes, APC
Tumor suppressor genes located in the 5q21 region on the long arm of human chromosome 5. The mutation of these genes is associated with familial adenomatous polyposis (ADENOMATOUS POLYPOSIS COLI) and GARDNER SYNDROME, as well as some sporadic colorectal cancers.
Gastrointestinal Neoplasms
Leukemia P388
Meningioma
A relatively common neoplasm of the CENTRAL NERVOUS SYSTEM that arises from arachnoidal cells. The majority are well differentiated vascular tumors which grow slowly and have a low potential to be invasive, although malignant subtypes occur. Meningiomas have a predilection to arise from the parasagittal region, cerebral convexity, sphenoidal ridge, olfactory groove, and SPINAL CANAL. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2056-7)
Genes, p53
Antibiotics, Antineoplastic
Chemical substances, produced by microorganisms, inhibiting or preventing the proliferation of neoplasms.
Predictive Value of Tests
In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.
Mucin-1
Carbohydrate antigen elevated in patients with tumors of the breast, ovary, lung, and prostate as well as other disorders. The mucin is expressed normally by most glandular epithelia but shows particularly increased expression in the breast at lactation and in malignancy. It is thus an established serum marker for breast cancer.
Prospective Studies
Sezary Syndrome
A form of cutaneous T-cell lymphoma manifested by generalized exfoliative ERYTHRODERMA; PRURITUS; peripheral lymphadenopathy, and abnormal hyperchromatic mononuclear (cerebriform) cells in the skin, LYMPH NODES, and peripheral blood (Sezary cells).
Fluorodeoxyglucose F18
The compound is given by intravenous injection to do POSITRON-EMISSION TOMOGRAPHY for the assessment of cerebral and myocardial glucose metabolism in various physiological or pathological states including stroke and myocardial ischemia. It is also employed for the detection of malignant tumors including those of the brain, liver, and thyroid gland. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1162)
Killer Cells, Natural
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.
Lymphoma, Non-Hodgkin
Any of a group of malignant tumors of lymphoid tissue that differ from HODGKIN DISEASE, being more heterogeneous with respect to malignant cell lineage, clinical course, prognosis, and therapy. The only common feature among these tumors is the absence of giant REED-STERNBERG CELLS, a characteristic of Hodgkin's disease.
Antineoplastic Agents, Alkylating
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)
Neurofibromatosis 1
An autosomal dominant inherited disorder (with a high frequency of spontaneous mutations) that features developmental changes in the nervous system, muscles, bones, and skin, most notably in tissue derived from the embryonic NEURAL CREST. Multiple hyperpigmented skin lesions and subcutaneous tumors are the hallmark of this disease. Peripheral and central nervous system neoplasms occur frequently, especially OPTIC NERVE GLIOMA and NEUROFIBROSARCOMA. NF1 is caused by mutations which inactivate the NF1 gene (GENES, NEUROFIBROMATOSIS 1) on chromosome 17q. The incidence of learning disabilities is also elevated in this condition. (From Adams et al., Principles of Neurology, 6th ed, pp1014-18) There is overlap of clinical features with NOONAN SYNDROME in a syndrome called neurofibromatosis-Noonan syndrome. Both the PTPN11 and NF1 gene products are involved in the SIGNAL TRANSDUCTION pathway of Ras (RAS PROTEINS).
Macrophages
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)
Plasmacytoma
Testicular Neoplasms
Tumors or cancer of the TESTIS. Germ cell tumors (GERMINOMA) of the testis constitute 95% of all testicular neoplasms.
Mesothelioma
A tumor derived from mesothelial tissue (peritoneum, pleura, pericardium). It appears as broad sheets of cells, with some regions containing spindle-shaped, sarcoma-like cells and other regions showing adenomatous patterns. Pleural mesotheliomas have been linked to exposure to asbestos. (Dorland, 27th ed)