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O6-benzylguanine
A guanine analogue with antineoplastic activity. O(6)-benzylguanine binds the DNA repair enzyme O(6)-alkylguanine DNA alkyltransferase (AGT), transferring the benzyl moiety to the active-site cysteine and resulting in inhibition of AGT-mediated DNA repair. Co-administration of this agent potentiates the effects of other chemotherapeutic agents that damage DNA. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

oblimersen
A phosphorothioate antisense oligonucleotide. Targeted to the initiation codon region of the bcl-2 mRNA, oblimersen inhibits bcl-2 mRNA translation, resulting in decreased expression of the bcl-2 protein, an apoptotic inhibitor expressed in some types of cancer and linked to tumor drug resistance. This agent may enhance the efficacy of standard cytotoxic chemotherapy. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

octreotide acetate
The acetate salt of a synthetic long-acting cyclic octapeptide with pharmacologic properties mimicking those of the natural hormone somatostatin. Octreotide is a more potent inhibitor of growth hormone, glucagon, and insulin than somatostatin. Similar to somatostatin, this agent also suppresses the luteinizing hormone response to gonadotropin-releasing hormone, decreases splanchnic blood flow, and inhibits the release of serotonin, gastrin, vasoactive intestinal peptide (VIP), secretin, motilin, pancreatic polypeptide, and thyroid stimulating hormone. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

octreotide pamoate
A synthetic long-acting octapeptide analogue of endogenous somatostatin. Octreotide pamoate binds to somatostatin receptors expressed by some neuroendocrine and non-neuroendocrine tumor cells, thereby initiating somatostatin receptor-mediated apoptosis. Other possible antineoplastic activities of this agent include suppression of tumor angiogenesis and tumor growth-promoting insulin-like growth factor 1 (IGF-1). Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

Oestromon
(Other name for: diethylstilbestrol)

ofatumumab
A fully human, high-affinity IgG1 monoclonal antibody directed against the B cell CD20 cell surface antigen with potential antineoplastic activity. Ofatumumab binds specifically to CD20 on the surfaces of B cells, triggering complement-dependent cell lysis (CDCL) and antibody-dependent cell-mediated cytotoxicity (ADCC) B cells overexpressing CD20. The CD20 antigen, found on over 90% of B cells of B cell lymphomas and other B cells of lymphoid tumors of B cell origin, is a non-glycosylated cell surface phosphoprotein that acts a calcium ion channel; it is exclusively expressed on B cells during most stages of B cell development. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

ofloxacin
A fluoroquinolone antibacterial antibiotic. Ofloxacin binds to and inhibits bacterial topoisomerase II (DNA gyrase) and topoisomerase IV, enzymes involved in DNA replication and repair, resulting in cell death in sensitive bacterial species. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

oglufanide disodium
The disodium salt of a synthetic form of a naturally-occurring dipeptide consisting of L-glutamic acid and L-tryptophan with potential antiangiogenic and potential immunomodulating activities. Oglufanide inhibits vascular endothelial growth factor (VEGF), which may inhibit angiogenesis. This agent has also been reported to stimulate the immune response to hepatitic C virus and intracellular bacterial infections. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

OGX-011
A mixed-backbone antisense oligodeoxynucleotide with chemosensitizing properties. OGX-011 inhibits testosterone-repressed prostate message-2 (TRPM-2). Administration of OGX-011 abrogates the anti-apoptotic effect of TRPM-2, thereby sensitizing cells to chemotherapy and resulting in tumor cell death. TRPM-2 is an anti-apoptotic clusterin that is overexpressed by prostate cancer cells and is associated with chemoresistance. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

olanzapine
A synthetic derivative of thienobenzodiazepine with antipsychotic, antinausea, and antiemetic activities. As a selective monoaminergic antagonist, olanzapine binds with high affinity binding to the following receptors: serotoninergic, dopaminergic, muscarinic M1-5, histamine H1, and alpha-1-adrenergic receptors; it binds weakly to gamma-aminobutyric acid type A, benzodiazepine, and beta-adrenergic receptors. The antinausea and antiemetic effects of this agent appear to be due to the blockade of 5-HT2 and 5-HT3 receptors for serotonin. Although its exact mechanism of action in schizophrenia is unknown, it has been proposed that olanzapine's antipsychotic activity is mediated through antagonism to dopamine D2 receptors with rapid ligand-receptor dissociation kinetics that help to minimize extrapyramidal symptoms (EPS). Olanzapine may also stimulate appetite. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

oligofructose-enriched inulin
A mixture of non-digestible carbohydrates, containing the fermentable plant fructans oligosaccharide and inulin, with potential prebiotic activity. Resisting hydrolysis by intestinal digestive enzymes, inulin and oligofructose serve as growth media and energy substrates for bifidobacteria in the colon; beneficial colonic commensal bacteria such as bifidobacteria may inhibit the colonization of the intestine by pathogenic bacteria and have been inplicated to inhibit colon carcinogenesis. Oligofructose-enriched inulin may be administered in combination with probiotic bifidobacteria. In addition, this agent may promote the absorption of calcium and magnesium from the gastrointestinal tract. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

oligonucleotide SPC2996
A synthetic antisense oligonucleotide against Bcl-2 messenger RNA with potential antitumor activity. Oligonucleotide SPC2996 binds to and inactivates Bcl-2 mRNA, thereby inhibiting the expression of Bcl-2 protein, promoting tumor cell apoptosis, and potentially enhancing the efficacy of standard cytotoxic chemotherapy. Linked to tumor drug resistance, the antiapoptotic protein Bcl-2 is upregulated in several types of cancers. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

omeprazole
A benzimidazole with selective and irreversible proton pump inhibition activity. Omeprazole forms a stable disulfide bond with the sulfhydryl group of the hydrogen-potassium (H+ - K+) ATPase found on the secretory surface of parietal cells, thereby inhibiting the final transport of hydrogen ions (via exchange with potassium ions) into the gastric lumen and suppressing gastric acid secretion. This agent exhibits no anticholinergic activities and does not antagonize histamine H2 receptors. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

Omnitarg
(Other name for: pertuzumab)

Oncaspar
(Other name for: pegaspargase)

OncoGel
(Other name for: PGLA/PEG copolymer-based paclitaxel)

OncoLAR
(Other name for: octreotide pamoate)

oncolytic adenovirus Ad5-Delta 24RGD
An adenovirus serotype 5 strain, selectively replication competent in cells defective in the Rb/p16 tumor suppressor pathway, with potential oncolytic activity. Oncolytic adenovirus Ad5-Delta 24RGD contains an integrin binding RGD-4C motif, allowing Coxsackie adenovirus receptor-independent infection of tumor cells, which are often deficient for Coxsackie and adenovirus receptors (CARs). Selectively replication competent in cells that are defective in retinoblastoma gene (Rb) or cyclin-dependent kinase inhibitor-2A (p16), active replication of oncolytic adenovirus Ad5-Delta 24RGD in tumor cells may induce oncolysis or cell lysis. As integral components of the late G1 restriction point, the Rb gene product and p16 are negative regulators of the cell cycle; ovarian cancer cells and non-small cell lung cancer cells may be defective in the Rb/p16 pathway. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

oncolytic adenovirus encoding GM-CSF
A recombinant oncolytic adenovirus encoding the immunohematopoietic cytokine granulocyte-macrophage colony stimulating factor (GM-CSF) with potential antineoplastic activity. Upon administration, the oncolytic adenovirus selectively infects and replicates in tumor cells, which may result in tumor cells lysis. Synergistically, GM-CSF (sargramostim) expressed by the oncolytic adenovirus may promote a cytotoxic T cell response against tumor cells harboring the oncolytic adenovirus, resulting in an immune-mediated tumor cell death. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

Onconase
(Other name for: ranpirnase)

Oncophage
(Other name for: vitespen)

OncoVEX GM-CSF
(Other name for: GM-CSF-encoding oncolytic herpes simplex virus)

ondansetron
A carbazole derivative with antiemetic activity. As a selective serotonin receptor antagonist, ondansetron competitively blocks the action of serotonin at 5HT3 receptors, resulting in suppression of chemotherapy- and radiotherapy-induced nausea and vomiting. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

ondansetron hydrochloride
The hydrochloride salt of the racemic form of ondansetron, a carbazole derivative and a selective, competitive serotonin 5-hydroxytrptamine type 3 (5-HT3) receptor antagonist with antiemetic activity. Although its mechanism of action has not been fully characterized, ondansetron appears to competitively block the action of serotonin at 5HT3 receptors peripherally in the gastrointestinal tract as well as centrally in the area postrema of the CNS, where the chemoreceptor trigger zone (CTZ) for vomiting is located, resulting in the suppression of chemotherapy- and radiotherapy-induced nausea and vomiting. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

ONTAK
(Other name for: denileukin diftitox)

ONYX-015
An E1B-55kDa-deleted adenovirus that is able to selectively replicate in and lyse TP53-deficient human tumor cells. After tumor cell lysis, released viruses infect neighboring tumor cells, tripping a chain of ONYX-015-mediated tumor cell cytotoxicity. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

opioid growth factor
An endogenous pentapeptide with potential antineoplastic and antiangiogenic activities. Opioid growth factor (OGF) binds to and activates the opioid growth factor receptor (OGFr), present on some tumor cells and vascular cells, thereby inhibiting tumor cell proliferation and angiogenesis. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

opium tincture
Also known as laudanum and formulated for oral administration, opium tincture is made of air-dried poppy (Papaver somniferum) latex and contains alkaloids such as morphine and codeine. As an antidiarrheal agent, it slows transit of intestinal contents by increasing intestinal smooth muscle tone and inhibiting motility; water is absorbed from fecal contents, decreasing diarrhea. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

Optison
(Other name for: perflutren protein-type A microspheres)

Ora-Testryl
(Other name for: fluoxymesterone)

Oracit
(Other name for: sodium citrate)

oral fludarabine phosphate
An oral formulation of the phosphate salt of fludarabine, a synthetic purine nucleoside analogue antimetabolite with antineoplastic activity. Fudarabine is preferentially transported into malignant cells and metabolized by deoxycytidine kinase to its active form, 2-fluoro-ara-ATP; 2-fluoro-ara-ATP competes directly with deoxyadenosine triphosphate (dATP) and inhibits alpha DNA polymerase, RNA reductase, and DNA primase, which may result in inhibition of DNA synthesis and cell death. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

oral microencapsulated diindolylmethane
An orally bioavailable microencapsulated formulation of diindolylmethane, an indole phytonutrient found in cruciferous vegetables, with estrogen-modulating, antiandrogenic, and potential antineoplastic activities. As a dimer of indole-3-carbinol, diindolylmethane (DIM) modulates estrogen balance by reducing the levels of 16-hydroxy estrogen metabolites and increasing the formation of beneficial 2-hydroxy estrogen metabolites. DIM also antagonizes androgen receptor activity, which may result in diminished cell proliferation and apoptosis in susceptible tumor cell populations. Pure DIM, which is relatively hydrophobic, is poorly absorbed after oral administration. This oral formulation, which consists of DIM, d-alpha-tocopheryl acid succinate, phosphatidylcholine, and silica microencapsulated in starch, significantly improves the gastrointestinal absorption of DIM. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

oral picoplatin
An oral preparation of picoplatin, a third generation platinum compound with antineoplastic activity. Designed to overcome platinum drug resistance, picoplatin alkylates DNA, forming both inter- and intra-strand cross-linkages, resulting in inhibition of DNA replication and RNA transcription and the induction of apoptosis. Because of the increase in steric bulk around the platinum center, there is a relative reduction in the inactivation of picoplatin by thiol-containing species such as glutathione and metallothionein in comparison to cisplatin. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

oral sodium phenylbutyrate
An orally active derivative of the short-chain fatty acid butyrate with potential antineoplastic activity. 4-Phenylbutyrate inhibits histone deacetylase, resulting in cell cycle gene expression modulation, reduced cell proliferation, increased cell differentiation, and apoptosis. This agent also initiates fragmentation of genomic DNA, resulting in decreased DNA synthesis and the inhibition of tumor cell migration and invasion. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

oral topotecan hydrochloride
An oral formulation of the hydrochloride salt of topotecan, a semisynthetic derivative of the quinoline alkaloid camptothecin, with potential antineoplastic activity. Topotecan selectively inhibits topoisomerase I activity by stabilizing topoisomerase I-DNA covalent complexes during the S phase of the cell cycle, thereby inhibiting religation of topoisomerase I-mediated single-strand DNA breaks and producing potentially lethal double-strand DNA breaks when encountered by the DNA replication machinery. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

Oralet
(Other name for: fentanyl citrate)

Oramorph SR
(Other name for: morphine sulfate)

Orasone
(Other name for: prednisone)

Orathecin
(Other name for: rubitecan)

oregovomab
A murine monoclonal antibody that attaches to the tumor-associated antigen CA125. Vaccination with monoclonal antibody B43.13 may stimulate a host cytotoxic immune response against tumor cells that express CA125. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

Orestralyn
(Other name for: ethinyl estradiol)

ormaplatin
A platinum(IV) analogue with antineoplastic activity. Ormaplatin alkylates DNA, forming both inter- and intra-strand platinum-DNA crosslinks, which result in inhibition of DNA replication and transcription and cell-cycle nonspecific cytotoxicity. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

Orplatna
(Other name for: satraplatin)

Orthoclone OKT3
(Other name for: muromonab-CD3)

OSI-7904L
A liposome-encapsulated formulation of the benzoquinazoline folate analog OSI-7904 with antineoplastic activity. As a thymidylate synthase inhibitor, OSI-7904 noncompetitively binds to thymidylate synthase, resulting in inhibition of thymine nucleotide synthesis and DNA replication. Liposome encapsulation improves the efficacy and increases the half-life of OSI-7904. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

Osmitrol
(Other name for: mannitol)

Ossirene
(Other name for: ammonium trichlorotellurate)

Ostarine
(Other name for: selective androgen receptor modulator GTx-024)

Ovaban
(Other name for: megestrol acetate)

OvaRex
(Other name for: oregovomab)

ovarian cancer peptide vaccine
A cancer vaccine comprised of synthetic peptides corresponding to naturally-occurring peptides derived from ovarian cancer cell antigens. Ovarian cancer peptide vaccine may elicit a cytotoxic T-cell response against tumor cells expressing the related ovarian cancer cell antigens. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

Ovrette
(Other name for: norgestrel)

oxaliplatin
An organoplatinum complex in which the platinum atom is complexed with 1,2-diaminocyclohexane (DACH) and with an oxalate ligand as a 'leaving group.' A 'leaving group' is an atom or a group of atoms that is displaced as a stable species taking with it the bonding electrons. After displacement of the labile oxalate ligand leaving group, active oxaliplatin derivatives, such as monoaquo and diaquo DACH platinum, alkylate macromolecules, forming both inter- and intra-strand platinum-DNA crosslinks, which result in inhibition of DNA replication and transcription and cell-cycle nonspecific cytotoxicity. The DACH side chain appears to inhibit alkylating-agent resistance. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

oxandrolone
A synthetic, anabolic steroid hormone analog of testosterone. Similar to testosterone, oxandrolone binds to and activates specific nuclear receptors. This agent may be used for testosterone replacement therapy in hypogonadal men, in HIV-wasting syndrome, and in other conditions in order to increase nitrogen retention and fat-free muscle mass. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

Oxitriptan
(Other name for: 5-hydroxytryptophan)

Oxsoralen-Ultra
(Other name for: methoxsalen)

OxyContin
(Other name for: oxycodone hydrochloride)

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