ABSTRACT
BACKGROUND/AIM: Lapathoside A, a phenylpropanoid ester, was isolated from the roots of buckwheat by searching for bioactive compounds against human pancreatic cancer cells. MATERIALS AND METHODS: Buckwheat root extracts, prepared by 70% ethanol, were separated into n-hexane, methylene chloride, ethyl acetate, n-butanol, and water fraction by solvent partitioning. Seven fractions were obtained from the ethyl acetate fraction by liquid chromatography, and fraction No. 6 contained lapathoside A. The effects of lapathoside A on Panc-1 and SNU-213 human pancreatic cancer cell lines were examined. RESULTS: The structure of lapathoside A was determined by liquid chromatography-mass spectrometry, liquid chromatography-tandem mass spectrometry, and nuclear magnetic resonance analysis. Next, we investigated whether lapathoside A has anticancer activity in human pancreatic cancer cell lines (PANC-1 and SNU-213). After treatment with 25 µM lapathoside A, viability of PANC-1 and SNU-213 cells decreased to about 40 and 27%, respectively. In addition, lapathoside A treatment also increased apoptosis while affecting the expression levels of apoptotic proteins. CONCLUSION: The effect of lapathoside A on apoptosis was confirmed in pancreatic cancer cell lines, supporting the application of lapathoside A in the treatment of pancreatic cancer.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Apoptosis/drug effects , Cinnamates/pharmacology , Fagopyrum , Pancreatic Neoplasms/drug therapy , Antineoplastic Agents, Phytogenic/isolation & purification , Apoptosis Regulatory Proteins/metabolism , Cell Line, Tumor , Cinnamates/isolation & purification , Fagopyrum/chemistry , Humans , Pancreatic Neoplasms/pathology , Signal TransductionABSTRACT
4-Hydroxybenzoate (4HBA) is a valuable platform intermediate for the production of commodity and fine chemicals, including protocatechuate, cis,cis-muconic acid, adipic acid, terephthalic acid, phenol, vanillin, and 4-hydroxybenzyl alcohol glycoside (gastrodin). Here we describe rational engineering of the shikimate and related pathways in Corynebacterium glutamicum ATCC13032 for over-producing 4HBA. As an approach to increase the carbon flux to 4HBA, we first introduced a mutated chorismate-pyruvate lyase (CPLpr) and feedback-resistant 3-deoxy-d-arabinoheptulosonate-7-phosphate synthases encoded by ubiCpr and aroFfbr/aroGfbr, respectively, from Escherichia coli along with blockage of carbon flux to the biosynthetic pathways for aromatic amino acids and the catabolic pathway for 4HBA by deletion of the genes trpE (encoding anthranilate synthase I), csm (chorismate mutase), and pobA (4HBA hydroxylase). In particular, CPLpr less sensitive to product inhibition was incorporated into the microorganism to enhance the conversion of chorismate to 4HBA. The subsequent steps involved expression of aroE (shikimate kinase) and aroCKB in the shikimate pathway and deletion of qsuABD coding for enzymes involved in the quinate/shikimate degradation pathway. Finally, to reduce accumulation of pathway intermediates, shikimate and 3-dehydroshikimate, shikimate-resistant AroK from Methanocaldococcus jannaschii was introduced. The resulting strain was shown to produce 19.0 g/L (137.6 mM) of 4HBA with a molar yield of 9.65% after 65 h in a fed-batch fermentation. The engineered strain can also be effectively applied for the production of other products derived from the shikimate pathway.
Subject(s)
Corynebacterium glutamicum/metabolism , Parabens/metabolism , Shikimic Acid/metabolism , Bacterial Proteins/genetics , Corynebacterium glutamicum/genetics , Escherichia coli/genetics , Metabolic Engineering , Oxo-Acid-Lyases/geneticsABSTRACT
Serum hepatitis B virus (HBV) markers are the most important data for epidemiological screening and clinical diagnosis of HBV infection, especially in endemic areas. We compared the results of the Roche Modular Analytics E170 assay, the Abbott Architect i2000 assay, and an immunoradiometric assay (IRMA) for HBV surface antigen (HBsAg), anti-HBV surface antigen (anti-HBs), HBV e antigen (HBeAg), and anti-HBV e antigen (anti-HBe). A number of serum samples (264, 263, 224, and 202 for HBsAg, anti-HBs, HBeAg, and anti-HBe, respectively) were studied. For samples giving discrepant results for HBeAg between methods, real-time PCR assays were performed. The concordance rates among the three methods were high for HBsAg (100%) and HBeAg (94.6), but low for anti-HBs (91.6%) and anti-HBe (82.2%). For anti-HBs, which could be measured quantitatively by the Modular E170 and Architect i2000 procedures, discrepant results were observed at low levels of anti-HBs. For anti-HBe, the positive rate was highest with Modular E170 (60.9%) followed by the IRMA kit (54.1%) and Architect i2000 (51.0%). This study shows substantial differences between the assay results by the three methods, which should be taken into account in determinations of serum HBV markers.
