antineoplastic /an·ti·neo·plas·tic/ (-ne″o-plas´tik)
Antineoplastic
antineoplastic
antineoplastic
1. inhibiting or preventing development of neoplasms; checking maturation and proliferation of malignant cells.
2. an agent that so acts.
an·ti·ne·o·plas·tic ( n t -n -pls t k, nt -)adj. Preventing the development, maturation, or spread of neoplastic cells. an ti·neo·plastic n. |
Antineoplastic
A drug used to inhibit the growth and spread of cancerous cells.
Mentioned in: Priapism
antineoplastic
[-nē′ōplas′tik]
Etymology: Gk, anti + neos, new, plasma, something formed
1 pertaining to a substance, procedure, or measure that prevents the proliferation of cells,
2 a chemotherapeutic agent that controls or kills cancer cells. Drugs used in the treatment of cancer are cytotoxic but are generally more damaging to dividing cells than to resting cells. Cycle-specific antineoplastic agents are more effective in killing proliferating cells than resting cells, and phase-specific agents are most active during a specific phase of the cell cycle. Most anticancer drugs prevent the proliferation of cells by inhibiting the synthesis of deoxyribonucleic acid (DNA) by various mechanisms. Alkylating agents, such as mechlorethamine HCl derivatives, ethylenimine derivatives, and alkyl sulfonates, interfere with DNA replication by causing cross-linking of DNA strands and abnormal pairing of nucleotides. Antimetabolites exert their action by interfering with the formation of compounds required for cell division. Methotrexate, folic acid analog, and 5-fluorouracil, a pyrimidine analog, inhibit enzymes required for the formation of the essential DNA constituent thymidine. 6-Mercaptopurine, a hypoxanthine analog, and 6-thioguanine, an analog of guanine, interfere with the biosynthesis of purines. VinBLAStine sulfate and vinCRIStine sulfate, alkaloids derived from the periwinkle plant, disrupt cell division by interfering with the formation of the mitotic spindle. Antineoplastic antibiotics, such as DOXOrubicin HCl, daunomycin, and mitomycin, block or inhibit DNA synthesis; dactinomycin and plicamycin interfere with ribonucleic acid synthesis. Cytotoxic chemotherapeutic agents may be administered via the oral or intravenous route or by infusion. All have untoward and unpleasant side effects and are potentially immunosuppressive and dangerous. Estrogens and androgens, although not considered antineoplastic agents, frequently cause tumor regression when administered in high doses to patients with hormone-dependent cancers.
antineoplastic
1. inhibiting the maturation and proliferation of malignant cells.
2. an agent having such properties.
antineoplastic therapy
a regimen of treatment aimed at destruction of malignant cells and utilizing a variety of chemical agents that directly affect cellular growth and development.
The chemicals and drugs used in the treatment of cancer may be divided into three groups. The first group, the alkylating agents, are capable of damaging the DNA of cells, thereby interfering with the process of replication. Among these drugs are chlorambucil, cyclophosphamide, mustine hydrochloride and triethylene thiophosphamide (thiotepa). The antibiotic actinomycin D (dactinomycin) is also included in this group.
The second type of drugs used in cancer chemotherapy are the antimetabolites. As the name suggests, these drugs interfere with the cancer cell's metabolism. Some replace essential metabolites without performing their function, while others compete with essential components by mimicking their functions and thereby inhibiting the manufacture of protein in the cell. Included in this group are cytosine arabinoside, floxuridine (FUDR), 5-fluorouracil (5-FU), mercaptopurine (6-MP), methotrexate and thioguanine.
The third group of chemicals employed in the treatment of cancer are 'natural products' that directly affect the mechanism of cell division. The plant alkaloids, e.g. vincristine and vinblastine, stop cell division at metaphase (a subphase in cell mitosis). The enzymes, e.g. L-asparaginase, starve tumor cells by catabolizing substances (e.g. asparagine) which they need for survival. Hormones change cell metabolism by making the cellular environment unfavorable for growth of certain tumors.
antineoplastic
adjective Referring to an antineoplastic agent or mechanism noun Chemotherapeutic agent, see there
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