Anti-tumour and pharmacokinetics study of 2-Formyl-8-hydroxy-quinolinium chloride as Galipea longiflora alkaloid analogue.

The quinolinium chloride salt of 8-hydroxyqinolinecarbaldehyde (2-Formyl-8-hydroxy-quinolinium chloride) was prepared as Galipea longiflora alkaloid analogue and its anticancer activity was evaluated both in vitro and in vivo. This chloride salt was found to show certain degree of selectivity between hepatoma cells and normal hepatocytes in vitro. Athymic nude mice Hep3B xenograft model further demonstrated that this 2-Formyl-8-hydroxy-quinolinium chloride could execute strong anti-tumour activity with the identification of extensive necrotic feature from the tumour xenograft and limited adverse toxicological effect.

Preparation of Galipea officinalis Hancock type tetrahydroquinoline alkaloid analogues as anti-tumour agents.

The preparation of chiral tetrahydroquinolines using Ir-catalysed asymmetric hydrogenation and their possible cytotoxic potential anti-cancer activity were reported. Both of the in vitro cytotoxicity assay on a series of human cancer cell lines including A549 small cell lung cancer, MDA-MB-231 breast cancer, SaoS2 sacroma, SKHep-1 hepatoma and Hep3B hepatocellular carcinoma as well as in vivo animal model using Hep3B hepatocellular tumour xenograft on athymic nude mice suggest that 1,2,3,4-tetrahydroquin-8-ol is a potential anti-tumour alkaloid which may be further developed as a novel cancer chemotherapeutic agent.

In vivo anti-tumour activity of corilagin on Hep3B hepatocellular carcinoma.

We have investigated the potential in vivo anti-tumour activity of corilagin using the Hep3B hepatocellular carcinoma cell line and an athymic nude mice xenograft model. The purity of corilagin was confirmed by high performance liquid chromatographic analysis. Corilagin was administrated intraperitoneally for a continuous period of 7 days at a concentration of 15 mg/kg of body weight per day. A significant inhibition of tumour growth was observed when treated mice are compared with control groups. Furthermore, analysis of enzymes markers of liver function, including alanine aminotransferase and asparate aminotransferase, suggested that current therapeutic dosage of corilagin did not exert adverse effect on liver. Our observations support the view that corilagin is considerably effective to retard the in vivo growth of xenografted Hep3B hepatocellular carcinoma.

Novel use of silymarin as delayed therapy for acetaminophen-induced acute hepatic injury.

AIM: Recently, we have demonstrated that silymarin has a comparable pharmaceutical activity as Phyllanthus urinaria extract when used to rescue mice from acetaminophen-induced acute liver injury. In the present study, we further compared the therapeutic action of silymarin with N-acetyl cysteine (commonly used in clinical practice for emergency treatments) as a rescuer in mice after administering a lethal dose of acetaminophen for 24 h. METHODS: Acute liver injury was induced in the treatment groups by intraperitoneally administered acetaminophen at a dose of 550 mg/kg body weight on day 1. The control group received an equal volume of physiological saline intraperitoneally. From day 2 to 4, the treatment groups received various doses of silymarin or N-acetyl cysteine orally once daily, while the control group and the acetaminophen group received an equal volume of water orally. The mortality rate was recorded in all groups. On day 5, all mice were sacrificed for examination. RESULTS: Silymarin greatly improved the counteracting effects on mortality rate as compared to N-acetyl cysteine. CONCLUSION: Silymarin should be further considered as an antidote for patients with acetaminopheninduced acute hepatic injury and delayed treatment.

The preparation of bi-functional organophosphine oxides as potential antitumor agents.

Following our previously reported pyridinyl phosphine oxides as antitumor agents, we targeted the commercially available C(2)-axial chiral organophosphine ligand catalysts, such as 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (BINAP) 1 and 2,2',6,6'-tetramethoxy-4,4'-bis(diphenylphosphino)-3,3'-bipyridine (P-Phos) 2 as a convenient source for producing organophosphine oxides as antitumor leads. Their corresponding chiral and racemic bi-phosphine oxides 3 and 4 can be obtained easily through a simple oxidation step with hydrogen peroxide, and their antitumor activities towards human hepatocellular carcinoma Hep3B cell line were reported. We found out that compound 3 shows stronger antitumor activity than that of 4, where axial chirality cannot improve their activity. Further athymic nude mice Hep3B xenograft model demonstrates the attractive in vivo antitumor potential of 3.

Synthesis, characterization and preliminary analysis of in vivo biological activity of chitosan/celecoxib microcapsules.

The use of chitosan as the wall of microcapsule designed for delivery of encapsulated celecoxib is reported. Microcapsules were characterised with respect to size and encapsulation efficiency of celecoxib. In vivo animals demonstrated that both free celecoxib administration and chitosan/celecoxib microcapsules administration lead to a significant inhibition of cyclooxygenase-2 protein expression in the hepatocytes when compared with vehicle control mice. Interestingly, microcapsule containing celecoxib showed a better inhibition of cyclooxygenase-2 protein expression when compared with a simple oral administration of free celecoxib. Gas-chromatography-mass-spectrometry analysis showed that in mice treated with free celecoxib or chitosan/celecoxib microcapsules, their plasma concentration of celecoxib was similar. Microcapsules-based biomaterials as oral drug delivery vehicles may help to improve the absorption efficiency of therapeutic drugs.

Synthesis of 9,9-dialkyl-4,5-diazafluorene derivatives and their structure-activity relationships toward human carcinoma cell lines.

A homologous set of 9,9-dialkyl-4,5-diazafluorene compounds were prepared by alkylation of 4,5-diazafluorene with the appropriate alkyl bromide and under basic conditions. The structures of these simple organic compounds were confirmed by spectroscopic techniques (FTIR, NMR, and FABMS). Their biological effects toward a panel of human carcinoma cells, including Hep3B hepatocellular carcinoma, MDAMB-231 breast carcinoma, and SKHep-1 hepatoma cells, were investigated; a structure-activity correlation was established with respect to the length of the alkyl chain and the fluorene ring structure. The relationship between the mean potency [log(1/IC(50))] and alkyl chain length was systematically studied. The results show that compounds with butyl, hexyl, and octyl chains exhibit good growth inhibitory effects toward these three human carcinoma cell lines, and the 9,9-dihexyl-4,5-diazafluorene further exhibits antitumor activity in athymic nude mice Hep3B xenograft models. For the structurally related dialkylfluorenes that lack the diaza functionality, in vitro cytotoxicity was not observed at clinically relevant concentrations.

Antitumor activity of diethynylfluorene derivatives of gold(I).

A list of diethynylfluorenes and their gold(I) derivatives have been studied for their antitumor activity as a function of their structure-activity relationships. End-capping the fluoren-9-one unit with gold(I) moieties could significantly strengthen the cytotoxic activity in vitro on three human cancer cell lines with induction of reactive oxygen species generation on Hep3B hepatocellular carcinoma cells and exhibit attractive antitumor activity from in vivo nude mice Hep3B xenograft model with limited adverse effects on vital organs including liver and kidney.