Screening assays for antioxidants and antiproliferative compounds
Provided are screening assays for identifying and evaluating compounds with antioxidant and/or antiproliferative activities.
1. A method of identifying a candidate compound with antioxidant or antiproliferative activity, or both, the method comprising:
contacting a test compound to a cell expressing neurotensin receptors on its cell surface;
contacting the cell with a neurotensin receptor ligand;
monitoring binding of the ligand to the cell; and
selecting the test compound as a candidate compound with antioxidant or antiproliferative activity if the test compound enhances binding of the ligand to the cell, relative to binding of the ligand to a cell of the same cell type that is not contacted with the test compound.
2. The method of claim 1 , wherein the test compound is a compound that belongs to a class selected from the group consisting of: dihydropyridines, polyphenols, flavonoids, isoprenoids, retinoids, inhibitors of mitochondrial function, inhibitors of glycolysis, inhibitors of glycogen synthase kinase, inhibitors of flavoprotein oxidases, iron/zinc chelators, inhibitors of lipoxygenases, inhibitors of protein kinase C, inhibitors of PI3-kinase, inhibitors of tyrosine kinases, and estrogen agonist.
3. The method of claim 1 , wherein the ligand is neurotensin.
4. The method of claim 1 , wherein the ligand is selected from the group consisting of neurotensin; a neurotensin fragment comprising neurotensin (8-13); neurotensin or an analog or fragment thereof with a substitution at one or more of the following positions: Arg 8, Arg 9, Pro 10, or Tyr 11, Ile 12, or Leu 13; a neurotensin with tryptophan substitution for Tyr 11; a neurotensin analog or fragment thereof MP-2530; Neuromedin-N; xenopsin; xenin; histamine releasing peptide; SR48692; SR142948A; and levocabastine.
5. The method of claim 1 , wherein the ligand is radiolabeled.
6. The method of claim 1 , wherein the cell is a cultured cell from a tumor selected from the group consisting of a Ewing's sarcoma, a myeloma, an astrocytoma, a lung tumor, a colon tumor, an ovarian tumor, a pancreatic tumor, and a prostate tumor.
7. The method of claim 1 , further comprising:
contacting a cancer cell with the selected candidate compound;
monitoring proliferation of the cancer cell; and
identifying the candidate compound as an antiproliferative agent if the candidate compound inhibits proliferation of the cancer cell relative to proliferation of a cancer cell of the same cell type that is not contacted with the candidate compound.
8. The method of claim 7 , wherein the cancer cell is a cell selected from the group consisting of a Ewing's sarcoma cell, a myeloma cell, an astrocytoma cell, a lung tumor cell, a colon tumor cell, an ovarian tumor cell, a pancreatic tumor cell, and a prostate tumor cell.
9. The method of claim 1 , wherein the method is repeated for a plurality of test compounds.
10. The method of claim 1 , wherein the cell is selected from the group consisting of a Ewing's sarcoma cell, a myeloma cell, an astrocytoma cell, a lung tumor cell, a colon tumor cell, an ovarian tumor cell, a pancreatic tumor cell, and a prostate tumor cell.
11. The method of claim 1 , wherein the test compound is selected as a candidate compound with antiproliferative activity if the test compound enhances binding of the ligand to the cell, relative to binding of the ligand to a cell of the same cell type that is not contacted with the test compound.
12. The method of claim 11 , wherein the test compound is a compound that belongs to a class selected from the group consisting of: dihydropyridines, polyphenols, flavonoids, isoprenoids, retinoids, inhibitors of mitochondrial function, inhibitors of glycolysis, inhibitors of glycogen synthase kinase, inhibitors of flavoprotein oxidases, iron/zinc chelators, inhibitors of lipoxygenases, inhibitors of protein kinase C, inhibitors of PI3-kinase, inhibitors of tyrosine kinases, and estrogen agonist.
13. The method of claim 11 , wherein the ligand is neurotensin.
14. The method of claim 11 , wherein the ligand is selected from the group consisting of neurotensin; a neurotensin fragment comprising neurotensin (8-13); neurotensin or an analog or fragment thereof with a substitution at one or more of the following positions: Arg 8, Arg 9, Pro 10, or Tyr 11, Ile 12, or Leu 13; a neurotensin with tryptophan substitution for Tyr 11; a neurotensin analog or fragment thereof MP-2530; Neuromedin-N; xenopsin; xenin; histamine releasing peptide; SR48692; SR142948A; and levocabastine.
15. The method of claim 11 , wherein the ligand is radiolabeled.
16. The method of claim 11 , wherein the cell is a cultured cell from a tumor selected from the group consisting of a Ewing's sarcoma, a myeloma, an astrocytoma, a lung tumor, a colon tumor, an ovarian tumor, a pancreatic tumor, and a prostate tumor.