antimetabolite

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Related to Antimetabolites: topoisomerase inhibitors, plant alkaloids

antimetabolite

 [an″te-, an″ti-mĕ-tab´o-līt]
1. a substance bearing a close structural resemblance to one required for normal physiological functioning, and exerting its effect by interfering with the utilization of the essential metabolite.
2. a class of antineoplastic agents consisting of antimetabolites of substances required for cell growth and replication; the interference with cell function is phase specific, largely in the S phase of the cell cycle. The group includes cladribine, cytarabine, floxuridine, fludarabine, fluorouracil, mercaptopurine, methotrexate, and thioguanine. See also antineoplastic therapy.

an·ti·me·tab·o·lite

(an'tē-me-tab'ō-līt),
A substance that competes with, replaces, or antagonizes a particular metabolite; for example, ethionine is an antimetabolite of methionine.

antimetabolite

/an·ti·me·tab·o·lite/ (an″te-) (an″ti-mĕ-tab´o-līt) a substance bearing a close structural resemblance to one required for normal physiological functioning, and exerting its effect by interfering with the utilization of the essential metabolite.

antimetabolite

(ăn′tē-mĭ-tăb′ə-līt′, ăn′tī-)
n.
A substance that closely resembles an essential metabolite and therefore inhibits physiological reactions involving that metabolite.

an′ti·met′a·bol′ic (-mĕt′ə-bŏl′ĭk) adj.

antimetabolite

[-mətab′əlīt]
Etymology: Gk, anti + metabole, change
a drug or other substance that is an antagonist to or resembles a normal human metabolite and interferes with its function in the body, usually by competing for its receptors or enzymes. Among the antimetabolites used as antineoplastic agents are the folic acid analog methotrexate and the pyrimidine analog fluorouracil. The antineoplastic mercaptopurine, an analog of the nucleotide adenine and the purine base hypoxanthine, is a metabolic antagonist of both compounds. Thioguanine, another member of a large series of purine analogs, interferes with nucleic acid synthesis. Cytarabine, used in the treatment of acute myelocytic leukemia, is a synthetic nucleoside that resembles cytidine and kills cells that actively synthesize deoxyribonucleic acid (DNA), apparently by inhibiting the enzyme DNA polymerase.

antimetabolite

Antimetabolic agent Pharmacology Any agent–eg, MTX, 6-mercaptopurine, thioguanine, 5-FU, gemcitabine that is a structural analogue of a native cell metabolite, which either inhibits the enzymes of a particular metabolic pathway or is incorporated during synthesis to produce defective product or prevents replication; anti-metabolites are used as chemotherapeutics, antivirals and as immunosuppressants, and include analogues of purines–eg azathioprine, pyrimidines, folic acid–eg aminopterin, MTX See Azathioprine, Methotrexate.

an·ti·me·tab·o·lite

(an'tē-mĕ-tab'ō-līt)
A substance that competes with, replaces, or antagonizes a particular metabolite; e.g., ethionine is an antimetabolite of methionine.

antimetabolite

An anticancer, or CYTOTOXIC, drug which acts by combining with essential enzymes within cancer cells so as to interfere with their metabolism and growth. To be useful, antimetabolites must be significantly more toxic to cancer cells than to normal cells.

Antimetabolite

A drug that interferes with a cell's growth or ability to multiply.
Mentioned in: Chemotherapy

antimetabolite

a substance bearing a close structural resemblance to one required for normal physiological functioning, and exerting its effect by interfering with the utilization of the essential metabolite.
References in periodicals archive ?
Long-term follow-up of trabeculectomy without antimetabolites in patients with uveitis.
Combinations of the antimetabolites gemcitabine or 5-fluoruracil with a microtubule-targeting drug have elicited synergistic and non-synergistic interactions (Johnson et al.
Figure 3: Cancer chemotherapy is evolving toward more selective approaches, with the share of cell messengers expected to increase 2008: $50 billion Non selective cytotoxics anticancers Alkylating agents ~10% Antimetabolities ~9% Antibiotics ~2% Microtubule Inhibitors ~10% Topoisimerase ~3% Hormonal therapies Hormonal therapy ~16% Selective anticancers Cell messengers ~50% 2013: $90 billion Non selective cytotoxics anticancers Alkylating agents ~7% Antimetabolites ~7% Antibiotics ~1% Microtubule Inhibitors ~7% Topoisimerase ~2% Hormonal therapies Hormonal therapy ~11% Selective anticancers Cell messengers ~63% Share of small molecule-based therapies (% of total anticancer sales) ~65% ~55% Note: Table made from pie chart.
Antimetabolites are classified according to the substances with which they interfere and include the folic acid antagonist Methotrexate, pyrimidine antagonists such as 5-Fluorouracil (5-FU), and purine antagonists such as 6-Mercaptopurine.
congenital immunodeficiency, HIV infection [vaccinate as close to diagnosis as possible when CD4 cell counts are highest], leukemia, lymphoma, multiple myeloma, Hodgkin disease, generalized malignancy, or organ or bone marrow transplantation); chemotherapy with alkylating agents, antimetabolites, or long-term systemic corticosteroids; and cochlear implants.
Antimetabolites are a broad class of drugs that interferes with the basic metabolism of cancer cells.
Other conditions include diabetes, heart disease, chronic pulmonary disease, chronic liver disease (including alcoholism), congenital immunodeficiency, leukemia, lymphoma, generalized malignancy, therapy with alkylating agents, antimetabolites, radiation or large amounts of corticosteroids, renal failure/ end stage renal disease, recipients of hemodialysis or clotting factor concentrates, asplenia including elective splenectomy, terminal complement component deficiencies, and HIV infection.
In contrast, 13% of the patients who received antimetabolites such as methotrexate, 5-fluorouracil, and cytarabine, developed restenosis.
The growth spurt will be fueled by the development of new drugs with fewer side effects and prophylactic uses of acute immunosuppressive therapies such as novel antimetabolites, monoclonal, and polyclonal antibodies, which will increase the success of transplants, the company reports.
He starts with Paul Ehrlich's antitreponemal arsenicals and ends with the antisense agents now in early clinical trials for the treatment of autoimmune diseases and cancer, covering in the process the development of antibacterial and antiviral agents, vaccines, antimetabolites, and hormone-based antineoplastic agents.
For caregivers and their patients, the therapeutic area that is at the forefront of attempts to mitigate exposure to cytotoxic drugs is clinical oncology, a field that - in spite of promising new drugs based on therapeutic antibodies - continues to rely heavily on antineoplastics, a class that includes alkylating agents and antimetabolites, to treat a wide range of cancers.