ABSTRACT
Bioassay-directed separation of the methylene chloride extracts from the wood of Liriodendron chinense led to the isolation of six sesquiterpenes, tulipinolide (1), alpha-liriodenolide (2), beta-liriodenolide (3), lipiferolide (4), 11,13-dehydrolanuginolide (5), and tulipinolide diepoxide (6). Compounds 1-6 have not been found previously in L. chinense. The structures of the compounds were established on the basis of NMR spectroscopic data. All the compounds exhibited quinone reductase (QR)-inducing activity in Hepa lclc7 cells.
Subject(s)
Liriodendron/chemistry , Quinone Reductases/chemistry , Sesquiterpenes/chemistry , Animals , Mice , Nuclear Magnetic Resonance, Biomolecular , Plant Extracts/chemistry , Quinone Reductases/isolation & purification , Quinone Reductases/pharmacology , Sesquiterpenes/isolation & purification , Sesquiterpenes/pharmacology , Wood/chemistryABSTRACT
Lung adenocarcinoma has replaced squamous cell lung carcinoma as the most frequent histological subtype in lung cancers. However, genetic factors that affect cancer susceptibility are much less understood in adenocarcinoma than in squamous cell carcinoma. In this study, polymorphisms in five genes involved in the metabolism of carcinogens or in the repair of damaged DNA in lung cells, NQO1-Pro187Ser, GSTT1-positive/null, GSTM1-positive/null, CYP1A1-Ile462Val, and OGG1-Ser326Cys, were examined for association with lung adenocarcinoma risk in a case-control study of 198 patients and 152 control subjects. The NQO1 and GSTT1 polymorphisms were associated with lung adenocarcinoma risk with adjusted odds ratio of 2.15 for the NQO1-Pro/Pro genotype versus the Ser/Ser genotype and adjusted odds ratio of 1.61 for the GSTT1-null genotype versus the positive genotype, respectively. Furthermore, individuals with the combined genotype of NQO1-Pro/Pro and GSTT1-null showed greater risk compared with those of NQO1-Ser/Ser and GSTT1-positive. In contrast, significant association was not observed for the GSTM1, CYP1A1, and OGG1 polymorphisms with lung adenocarcinoma risk, although several studies have shown their implication in the risk for squamous cell lung carcinoma. The result indicates that the NQO1-Pro/Pro and GSTT1-null genotypes are risk factors for lung adenocarcinoma development, and that the genetic factors for susceptibility to adenocarcinoma are different from those to squamous cell carcinoma. The enhanced risk of the NQO1-Pro/Pro genotype combined with the GSTT1-null genotype was more evident in smokers than in nonsmokers. Therefore, carcinogens in tobacco smoke, which are activated by NQO1 and detoxified by GSTT1, could have a role in lung adenocarcinoma development.
Subject(s)
Adenocarcinoma/etiology , Adenocarcinoma/genetics , Carcinoma, Non-Small-Cell Lung/etiology , Carcinoma, Non-Small-Cell Lung/genetics , Genetic Predisposition to Disease , Glutathione Transferase/genetics , Lung Neoplasms/etiology , Lung Neoplasms/genetics , Polymorphism, Genetic , Quinone Reductases/genetics , Adult , Carcinogens/metabolism , Case-Control Studies , DNA Damage , Female , Genotype , Glutathione Transferase/pharmacology , Humans , Male , Middle Aged , Odds Ratio , Quinone Reductases/pharmacology , Risk Factors , Smoking/adverse effectsABSTRACT
Synthesized 5-arylamino-2-methyl-4,7-dioxobenzothiazoles 3a-3o were evaluated for modulation of NAD(P)H: quinone oxidoreductase (NQO1) activity with the cytosolic fractions derived from cultured human lung cancer cells and their cytotoxicity in cultured several human solid cancer cell lines. The 4,7-dioxobenzothiazoles affected the reduction potential by NQO1 activity and showed a potent cytotoxic activity against human cancer cell lines. The tested compounds 3a, 3b, 3g, 3h, 3n and 3o were considered as more potent cytotoxic agents, and comparable modulators of NQO1 activity.