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(61)Cu-ATSM  
A lipophilic copper(II)bis(thiosemicarbazone) labeled with the positron-emitting isotope (61)Cu with hypoxia-selective and radioisotopic activities. With a high membrane permeability and redox potential, (61)Cu-ATSM easily enters and selectively resides in hypoxic cells. The extent of (61)Cu-ATSM retention in tissue is inversely related to the state of tissue oxygenation allowing the quantitation of tissue hypoxia with positron emission tomography (PET). Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

1-methyl-d-tryptophan  
A methylated tryptophan with anti-immunosuppressive activity. 1-methyl-d-tryptophan inhibits the enzyme indoleamine 2,3-dioxygenase (IDO), which degrades the essential amino acid tryptophan, and may increase or maintain tryptophan levels important to T cell function. Tryptophan depletion is associated with immunosuppression involving T cell arrest and anergy. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

11C topotecan  
A semisynthetic derivative of camptothecin, a cytotoxic, quinoline-based alkaloid extracted from the Asian tree Camptotheca acuminata radiolabeled with carbon 11 (11C) with antineoplastic and radiotracer properties. During the S phase of the cell cycle, topotecan inhibits topoisomerase I activity by stabilizing the cleavable complex between topoisomerase I and DNA, resulting in DNA breaks that inhibit DNA replication and trigger apoptotic cell death. Quantitation of 11C topotecan accumulated in tumor tissues by positron emission tomography (PET) may help predict responses to topotecan therapy. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

123-I-MIP-1072  
An iodine 123-radiolabled small molecule that exhibits high affinity for prostate-specific membrane antigen (PSMA) with potential use in molecular imaging. 123-I-MIP-1072, a radiolabeled glutamate-urea-lysine analogue, selectively binds PSMA, which allows imaging of PSMA-expressing prostate cancer cells with gamma scintigraph. PSMA is a transmembrane glycoprotein highly expressed by malignant prostate epithelial cells and vascular endothelial cells of various solid tumors. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

123-I-MIP-1095  
An iodine 123-radiolabled small molecule that exhibits high affinity for prostate-specific membrane antigen (PSMA) with potential use in molecular imaging. 123-I-MIP-1095, a radiolabeled glutamate-urea-lysine analogue, selectively binds PSMA, which allows imaging of PSMA-expressing prostate cancer cells with gamma scintigraph. PSMA is a transmembrane glycoprotein highly expressed by malignant prostate epithelial cells and vascular endothelial cells of various solid tumors. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

131-I-MIP-1145  
An iodine 131-radiolabeled small-molecule benzamide compound with potential antineoplastic activity. The benzamide moiety of 131-I-MIP-1145 binds to melanin, selectively delivering a cyotoxic dose of gamma and beta radiation to melanin-expressing tumor cells. Melanin pigments, polymer derivatives of the amino acid tyrosine, are over-expressed in approximately 40% of melanomas. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

131I-TM-601  
An iodine 131 (I 131) radioconjugate of the synthetic chlorotoxin (CTX) TM-601 with potential antiangiogenic and antineoplastic activities. CTX is a 36 amino acid neurotoxin found in the venom of the giant yellow scorpion Leiurus quinquestriatus that preferentially binds malignant cells of neuroectodermal origin. The recombinant version of this peptide, TM-601, is expressed in and purified from E. coli and then covalently linked to I 131 to produce 131I-TM-601. 131I-TM-601 binds to tumor cells of neuroectodermal origin and is internalized; administered once, it may be used as a radioimaging agent; repeated administration may result in a tumor-specific, cumulative radiocytotoxic dose of I 131. In addition, TM-601 alone, similar to native CTX, may inhibit angiogenesis due to its ability to bind to and inhibit matrix metalloproteinase 2 (MMP-2), an endopeptidase involved in tissue remodeling processes such as angiogenesis. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

18F-FHBG  
A fluorine-18-labeled acycloguanosine derivative substrate for herpes simplex virus type-1 thymidine kinase (HSV1-tk). 18F-FHBG is used as a reporter probe to image the expression of the herpes simplex virus type-1 thymidine kinase (HSV1-tk) gene in gene transfer therapy. HSV1-tk and and HSV1-tk-metabolized 18F-FHBG co-localize, allowing positron emission tomography (PET) localization of HSV1-tk gene-transfected tissue and the assessment of gene transfer efficiency. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

18F-fluoromethylcholine  
A radiotracer consisting of methylcholine labeled with the positron-emitting radioisotope fluorine F 18 (18F-FMCH) with potential imaging use. Upon administration, 18F-fluoromethylcholine incorporates into tumor cells through an active, carrier-mediated transport mechanism for choline and then is phosphorylated intracellularly by choline kinase, an enzyme frequently upregulated in human tumors, yielding phosphoryl 18F-fluoromethylcholine. In turn, phosphoryl 18F-fluoromethylcholine is integrated into phospholipids in the cell membrane as part of phosphatidylcholine. As the proliferation of cancer cells is much higher than normal cells, tumor cells exhibit an increased rate of 18F-FMCH uptake and incorporation, allowing tumor imaging with positron emission tomography (PET). Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

18F-fluoromisonidazole  
A radiofluorinated 2-nitroimidazole derivate with hypoxia-specific tracer activity. Misonidazole is reduced under hypoxic conditions and in reduced form covalently binds to macromolecules in hypoxic cells. 18F (fluorine-18) radiofluorination of misonidazole to form 18F-fluoromisonidazole allows radioisotopic imaging of reduced misonidazole bound to macromolecules in hypoxic cells. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

2'-F-ara-deoxyuridine  
A deoxyuridine prodrug with potential antineoplastic activity. Upon cellular uptake, 2’-F-ara-deoxyuridine (FAU) is phosphorylated by thymidine kinase to FAU monophosphate and subsequently methylated in the 5'-position by thymidylate synthase (TS) to its activated form, 1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl) 5-methyluracil monophosphate (FMAUMP). FMAUMP is incorporated into DNA leading to an inhibition of DNA synthesis and so cell growth. The catalytic activity of TS is critical to activation of FAU and subsequent incorporation into DNA. FAU may be beneficial in the case of tumors with high TS activity that are resistant to TS inhibitors. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

2-methoxyestradiol  
An orally bioavailable estradiol metabolite with potential antineoplastic activity. 2-Methoxyestradiol inhibits angiogenesis by reducing endothelial cell proliferation and inducing endothelial cell apoptosis. This agent also inhibits tumor cell growth by binding to tubulin, resulting in antimitotic activity, and by inducing caspase activation, resulting in cell cycle arrest in the G2 phase, DNA fragmentation, and apoptosis. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

2G-1 TCR retroviral vector-transduced lymphocytes  
A preparation of autologous human T-lymphocytes isolated from renal cell cancer (RCC) patient and transduced with 2G-1 TCR, a retroviral vector encoding the alpha and beta chains of a T-cell receptor that recognizes TNF-related apoptosis inducing ligand (TRAIL) bound to death receptor 4 (DR4), with potential immunostimulating and antineoplastic activities. After transduction, expansion in culture, and introduction into the RCC patient, 2G-1 TCR retroviral vector-transduced lymphocytes may stimulate a cytotoxic T lymphocyte (CTL) response against RCC cells with TRAIL bound to DR4 on their surfaces. TRAIL, a member of the TNF superfamily, is a homotrimeric type II membrane protein that rapidly induces oligomerization of receptor intracellular death domains and apoptosis in a variety of tumor cells when bound to its receptors; DR4 (TRAIL receptor 1), a member of the TNF receptor family, is overexpressed by a variety of malignant cell types. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

3'-C-ethynylcytidine  
A synthetic cytidine nucleoside containing a covalently bound ethynyl group with potential antineoplastic and radiosensitizing activities. 3'-C-ethynylcytidine is metabolized in tumor cells to ethynylcytidine triphosphate (ECTP), which inhibits RNA synthesis by competitive inhibition of RNA polymerases I, II and III; subsequently, RNase L is activated, resulting in apoptosis. RNase L is a potent antiviral and antiproliferative endoribonuclease that cleaves singled stranded RNA, causes 28s rRNA fragmentation, and activates Janus Kinase (JAK), a mitochondrial-dependent apoptosis signaling molecule. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

3'-deoxy-3'-[18F]fluorothymidine  
A radioconjugate consisting of a thymidine analogue radiolabeled with fluorine F 18, a positron emitting isotope. Phosphorylated by S-phase-specific thymidine kinase 1, 3'-deoxy-3'-[18F]fluorothymidine (18F-FLT) is trapped intracellularly by entering the salvage pathway of DNA synthesis without incorporation into DNA. 18F-FLT serves a marker of tumor cell proliferation for imaging with positron emission tomography (PET); as a marker of proliferation rather than metabolism, it is more specific to tumor tissue than 2-deoxy-2-[18F] fluoro-D-glucose (18F-FDG). This agent is metabolically stable, accumulates in the normal bone marrow and the liver, and does not cross the blood-brain barrier. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

3,4-diaminopyridine  
An organic compound derived from pyridine with potassium channel inhibition activity. 3,4-diaminopyridine inhibits potassium channel efflux, increasing the duration of the action potential, which results in an increase in the duration of calcium channel opening and enhanced acetylcholine (ACh) release. Increased ACh availability at the motor end plate allows muscles to contract. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

3,4-methylenedioxymethamphetamine  
A ring-substituted amphetamine derivative, structurally related to the hallucinogen mescaline, with entactogenic, neurotoxic, and motor-stimulatory activities. 3,4-methylenedioxymethamphetamine (MDMA) produces an acute, rapid enhancement in both the release of serotonin from and the inhibition of serotonin reuptake by serotonergic nerve endings in the brain. Once within the cell, MDMA depletes stores of tryptophan hydroxylase (TPH) via acute oxidative inactivation; in turn, depleted stores of TPH leave cell terminals open to damage from oxidative stress, possibly a source of MDMA neurotoxicity. This agent also induces norepinephrine, dopamine, and acetylcholine release and can act directly on a number of receptors, including alpha 2-adrenergic and 5-hydroxytryptamine (5-HT) 2A receptors. MDMA may suppress the dyskinesia associated with long-term use of L-dopamine (L-DOPA) without affecting the efficacy of L-DOPA treatment. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

3-deazauridine  
A synthetic analogue of nucleoside uridine lacking a ring nitrogen in the 3-position. 3-deazauridine inhibits cytidine synthase, thereby reducing intracellular levels of cytidine and deoxycytidine and disrupting DNA and RNA synthesis. This agent may trigger apoptosis and enhance differentiation of neoplastic cells.. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

4'-iodo-4'-deoxydoxorubicin  
An iodinated doxorubicin analogue with antiamyloid activity. 4'-Iodo-4'-deoxydoxorubicin (IDOX) binds with high affinity to five types of natural amyloid fibrils including immunoglobulin light chains, amyloid A, transthyretin (methionine-30 variant), ß-protein (Alzheimer), and ß2-microglobulin. This agent may inhibit fibril growth, increasing the solubility of amyloid tissue deposits and facilitating their clearance. IDOX has also been shown to insulin amyloid fibrillogenesis in vitro. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

4-hydroxytamoxifen  
A tamoxifen metabolite with both estrogenic and anti-estrogenic effects. 4-hydroxytamoxifen has a higher affinity for the estrogen receptor than tamoxifen, and functions as an antagonist in breast cancer cells. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

4-nitroestrone 3-methyl ether  
A synthetic derivative of estradiol. 4-nitroestrone 3-methyl ether inhibits estrogen sulfotransferase (EST), a progesterone-induced secretory endometrial enzyme which affects estrogen receptor levels. This agent has been shown to be an effective growth inhibitor of some chemically induced animal mammary tumors. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

5,10-methylenetetrahydrofolate  
A folate-based biomodulator with potential antineoplastic activity. 5,10-methylenetetrahydrofolate (MTHF) stabilizes the covalent binding of the fluorouracil metabolite 5-5-fluoro-2'-deoxyuridine-5'-O-monophosphate (FdUMP) to its target enzyme, thymidylate synthase, which results in inhibition of thymidylate synthase, depletion of thymidine triphosphate (TTP), a necessary constituent of DNA, and tumor cell death. Unlike leucovorin, MTHF, as the active form of folate, does not require metabolic activation and may increase the chemotherapeutic effects of fluorouracil with lower toxicity. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

5-[18F]fluorouracil  
The fluorine-18 (18F)-radiolabeled pyrimidine analog 5-fluorouracil (5-FU) with positron-emitting activity. Upon administration, 5-[18F]fluorouracil distribution in tumor tissue may be measured with positron emission tomography (PET). The degree of 5-[18F]fluorouracil uptake in tumor tissue may help to predict the response to 5-fluorouracil-based chemotherapy or to determine the response to other therapeutic agents used to treat 5-FU-sensitive tumors. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

5-hydroxytryptophan  
An aromatic amino acid with antidepressant activity. In vivo, 5-hydroxytryptophan (5-HTP) is converted into 5-hydroxytryptamine (5-HT or serotonin) as well as other neurotransmitters. 5-HTP may exert its antidepressant activity via conversion to serotonin or directly by binding to serotonin (5-HT) receptors within the central nervous system (CNS). Endogenous 5-HTP is produced from the essential amino acid L-tryptophan. Exogenous therapeutic 5-HTP is isolated from the seeds of the African plant Griffonia simplicifolia. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

50% oxygen/50% nitrous oxide premix  
An equimolar gas mixture of oxygen (O2) and nitrous oxide (N2O) with potential analgesic activity. Upon inhalation, 50% oxygen/50% nitrous oxide premix produces rapidly reversible analgesia. The exact mechanism through which nitrous oxide exerts its analgesic effect has yet to be fully elucidated, but it appears to be associated with the neuronal release of endogenous opioid peptides. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

6-azauridine  
A synthetic triazine analogue of uridine with antimetabolite activity. 6-azauridine inhibits de novo pyrimidine synthesis and DNA synthesis and is converted intracellularly into mono, di-, and triphosphate derivatives, which incorporate into RNA and inhibit protein synthesis. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

7-cyanoquinocarcinol  
A semisynthetic analogue of the Streptomyces melanovinaceus-derived tetracyclic antitumor antibiotic quinocarmycin with potential antineoplastic activity. Quinocarmycin belongs to the naphthyridinomycin/saframycin class of antitumor antibiotics. These antibiotics appear to act through DNA alkylation. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

7-hydroxystaurosporine  
A synthetic derivative of staurosporine with antineoplastic activity. 7-hydroxystaurosporine inhibits many phosphokinases, including the serine/threonine kinase AKT, calcium-dependent protein kinase C, and cyclin-dependent kinases. This agent arrests tumor cells in the G1/S of the cell cycle and prevents nucleotide excision repair by inhibiting the G2 checkpoint kinase chk1, resulting in apoptosis. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

8-hydroxyquinoline sulfate ointment  
An ointment formulation containing the sulfate salt of 8-hydroxyquinoline in a petrolatum and lanolin base with skin-protecting activity. Upon topical application, 8-hydroxyquinoline sulfate exhibits antiseptic activity while lanolin moisturizes and softens skin. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

851B gel  
A topical gel containing a peptide derived from the human papillomavirus (HPV). Application of 851B gel may stimulate the host immune system to trigger a cytotoxic T-lymphocyte response to cells that express HPV. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

852A  
A synthetic imidazoquinoline Toll-like receptor 7 (TLR7) agonist with immunostimulating and potential antitumor activities. TLR7 agonist 852A binds to and activates TLR7, thereby stimulating plasmacytoid dendritic cells (pDC) through the TLR7-MyD88-dependent signaling pathway. Activation of pDC results in secretion of interferon alpha, the production of proimflammatory cytokines, the upregulation of co-stimulatory molecules, and enhanced T and B-cell stimulatory responses. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

99mTc-DTPA-mannosyl-dextran  
A radiolabeled macromolecule consisting of the chelating agent diethylenetriamine pentaacetic acid (DTPA) and mannose each attached to a dextran backbone and labeled with metastable technetiumTc-99 (Tc-99m), with mannose binding and radioisotopic activities. Upon injection, the mannose moiety of 99mTc-DTPA-mannosyl-dextran binds to mannose-binding protein (MBP). As MBPs reside on the surface of dendritic cells and macrophages, this gamma-emitting macromolecule tends to accumulate in lymphatic tissue where it may be imaged using gamma scintigraphy. This agent exhibits rapid clearance from the injection site, rapid uptake and high retention within the first draining lymph node, and low uptake by the remaining lymph nodes. MBP is a C-type lectin that binds mannose or fucose carbohydrate residues, such as those found on the surfaces of many pathiogens, and once bound activates the complement system. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

[18F]-labeled substance P antagonist receptor quantifier  
A radioconjugate consisting of the positron emitting radioisotope fluorine F 18 conjugated to the substance P antagonist receptor quantifier (SPA-RQ) used in radioimaging. [18F]-labeled substance P antagonist receptor quantifier is an antagonist of the neurokinin 1 (substance P) receptor (NK1R) and can function as a positron emission tomography (PET) imaging agent for detecting NK1R-expressing cells and tissues. NK1Rs are frequently expressed on the plasma membranes of tumor cells from glioblastoma and breast and pancreatic carcinomas. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

[18F]-ML-10  
A small molecular-weight, malonic acid-based probe [(2-(5-fluoro-pentyl)-2-methyl-malonic acid or ML-10] labeled with the radioactive isotope fluorine F 18 with potential apoptosis radioimaging use. Upon administration, [F18]-ML-10 binds selectively to apoptotic cells due to apoptotic cell membrane features that differ from those of normal, healthy and necrotic cell membranes. Upon entering the apoptotic cell, this agent accumulates within the cytoplasm where it can be imaged using positron emission tomography (PET). Detection of apoptotic cells using this imaging technology may be useful in monitoring tumor responses to cytotoxic therapies. ML-10 appears to mimic the alkyl-malonic acid motif present in gamma -carboxyglutamic (Gla), an amino acid that plays a crucial role in the binding of clotting factors to negatively-charged phospholipids exposed on the surfaces of apoptotic cells. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

[F-18]HX4  
A 2-nitroimidazole labeled with the positron-emitting radioisotope fluorine F 18. HX4, the 2-nitroimidazole moiety of [F-18]HX4, is selectively bioreduced and bound in hypoxic tumor cells, permitting the imaging of hypoxic tumor cells with positron emission tomography (PET). Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)

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