beta-carotene and Lymphoma--B-Cell

Continuing our search for cancer chemopreventive agents from natural sources, we examined constituents of the stem bark of Calophyllum brasiliense. Three new 4-substituted coumarins named brasimarins A (2), B (3), and C (4) were isolated and characterized, along with 11 known coumarins belonging to the calanolides or inophyllums. We also discuss the inhibitory effects of these coumarins on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells.

Topics: Anticarcinogenic Agents; Antigens, Viral; Brazil; Calophyllum; Cells, Cultured; Coumarins; Drug Screening Assays, Antitumor; Humans; Lymphoma, B-Cell; Nuclear Magnetic Resonance, Biomolecular; Plant Bark; Plants, Medicinal; Tetradecanoylphorbol Acetate

Six new rearranged 3,4-seco-tirucallane-type triterpenoids (1-6) have been isolated from the diethyl ether extract of the pollen grains of sunflower (Helianthus annuus). These compounds were evaluated with respect to their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) induced by the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA) in Raji cells. All of the compounds tested showed potent inhibitory effects on EBV-EA activation (97-100% inhibition at 1 x 10(3) mol ratio/TPA).

Topics: Antigens, Viral; Helianthus; Humans; Japan; Lymphoma, B-Cell; Nuclear Magnetic Resonance, Biomolecular; Plants, Medicinal; Pollen; Tetradecanoylphorbol Acetate; Triterpenes; Tumor Cells, Cultured; Virus Activation

Five new cinnamylphenols (1,3-diphenylpropenes), dalberatins A (1), B (2), C (3), D (4), and E (5), were isolated from plants of the Dalbergia species. They were characterized and tested for their inhibitory activities against Epstein-Barr virus early antigen activation induced by 12-O-tetradecanoylphorbol-13-acetate in Raji cells. The cinnamylphenols were found to show remarkably potent activities. The result of the present investigation indicated that some of these cinnamylphenols might be valuable as potential cancer chemopreventive agents (anti-tumor promoters).

Topics: Anticarcinogenic Agents; Antigens, Viral; Dalbergia; Humans; Lymphoma, B-Cell; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Phenols; Plants, Medicinal; Tetradecanoylphorbol Acetate; Thailand

A new triterpene acid, lucidenic acid P (1a), and two new triterpene acid methyl esters, methyl lucidenates P (1b) and Q (2b), were isolated and characterized from the fruiting body of the fungus Ganoderma lucidum. Their structures were elucidated on the basis of spectroscopic methods. In addition, eight known triterpene acids, lucidenic acids A (3a), C (4a), D(2) (5a), E(2) (6a), and F (7a) and ganoderic acids E (9a), F (10a), and T-Q (11a), and six known triterpene acid methyl esters, methyl lucidenates A (3b), D(2) (5b), E(2) (6b), F (7b), and L (8b) and methyl ganoderate F (10b), were isolated and identified from the fungus. All of the triterpenoids, with the exception of 7a, were evaluated with respect to their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, which is known to be a primary screening test for antitumor promoters. All of the compounds tested showed potent inhibitory effects on EBV-EA induction (96-100% inhibition at 1 x 10(3) mol ratio/TPA).

Topics: Antigens, Viral; Humans; Japan; Lymphoma, B-Cell; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Reishi; Tetradecanoylphorbol Acetate; Triterpenes

Topics: Animals; Antioxidants; Apoptosis; beta Carotene; Humans; Lymphoma, B-Cell; Oxidation-Reduction; Proto-Oncogene Proteins c-bcl-2; Vitamin A