The isothiocyanate produced from glucomoringin inhibits NF-kB and reduces myeloma growth in nude mice in vivo.

Glucosinolates (GLs), natural compounds extracted from Brassicaceae and precursors of isothiocyanates (ITCs), have been studied in the last decades mostly due to their chemopreventive activity and, more recently, for their potential use as novel chemotherapeutics. The aim of the present study was to investigate the in vitro and in vivo activity of glucomoringin (GMG), an uncommon member of the GLs family, and to compare it with glucoraphanin (GRA), one of the most studied GL. We have evaluated the potency of both compounds in inducing cell death, cell cycle perturbations, apoptosis, NF-kB inhibition and GST-pi activity in human carcinoma cells with different GST-pi contents as well as in human multiple myeloma and leukaemia cell lines. GMG-derived ITC (GMG-ITC) showed to be more effective compared to GRA-derived ITC (Sulforaphane), especially in inhibiting NF-kB activity and inducing apoptosis through a caspase-dependent pathway; these effects were more pronounced in myeloma cells, in which we could also observe a long lasting growth inhibitory effect, probably due to NF-kB inhibition, which is considered essential for myeloma cell survival. Both GLs were able to induce cell death in the muM range in all tested cell lines but caused cell cycle perturbations only in myeloma cells; they were also able to modulate the GST/GSH pathway by causing a 3-fold increase in GST-pi activity in MCF7 cells. In vivo study showed that pure GMG-ITC was only slightly active in a carcinoma mice model, whereas it had significant antitumoral activity in a myeloma model, causing little toxicity.

Development and validation of a LC-MS/MS method for the determination of the novel oral 1,14 substituted taxane derivatives, IDN 5738 and IDN 5839, in mouse plasma and its application to the pharmacokinetic study.

Two LC-ESI-MS and CID-MS/MS methods were developed and validated for pharmacokinetic studies of the novel oral taxane derivatives IDN 5738 and IDN 5839, used for preclinical evaluation in mice. The analysis requires 100muL of plasma sample, involves the addition of an internal standard and protein precipitation with 0.1% HCOOH in acetonitrile. The HPLC separation was obtained on Sunfire C18 column and Selected Reaction Monitoring technique was used to quantify the taxanes. The recoveries were more than 90%; the methods were linear over the validated concentrations range of 25-1500ng/mL for IDN 5738 and 25-5000ng/mL for IDN 5839 and had a limit of detection of 0.14 and 0.25ng/mL, respectively. The inter-day coefficient of variation (CV%) of the calibration standards ranged between 1.3 and 7.2% for IDN 5738 and between 0.0 and 9.0% for IDN 5839 and the mean accuracy was in the range 85.3-112.0% for IDN 5738 and between 80.0 and 111.0% for IDN 5839. Moreover, analysing quality control plasma samples on three different days, the methods resulted precise and accurate showing intra- and inter-day CV within 12% for both analytes, and accuracy of 92.0-113.3% and 85.9-105.7% for IDN 5738 and IDN 5839, respectively. With these methods, we studied for the first time, the pharmacokinetics of the two taxanes showing for both, good oral bioavailability (>50%).

Biological properties of IDN5174, a new synthetic camptothecin with the open lactone ring.

A series of water-soluble camptothecins obtained by linking a spermidine moiety to the 21-position of the open form through an amidic bond have been tested for their biochemical and biological activities. Growth inhibition assay on the human non-small cell lung cancer carcinoma NCI-H460 cell line revealed that the camptothecin analogues were less potent than topotecan and SN38 after 1 hour of treatment. The potency increased after 72 hours of exposure, being similar to that of reference camptothecins. The analysis of topoisomerase I-mediated DNA cleavage using the purified enzyme indicated that the novel camptothecin analogues retained ability to poison topoisomerase I and displayed the same cleavage pattern of SN38. Persistence of the DNA cleavage was comparable with that of SN38. Stabilization of the cleavable complex was not the result of hydrolysis of the N-C bond between polyamine and the drug because no free camptothecin was recovered at the end of DNA cleavage in presence of IDN5174, the analogue selected for detailed studies. IDN5174 exhibited an antitumor activity comparable with that of topotecan and irinotecan against NCI-H460 tumor xenograft. The pharmacokinetics in mice showed a favorable disposition in tumor tissue with low amount of camptothecin detectable in plasma and tumor (around 5-10%), thus supporting the efficacy of intact IDN5174. In conclusion, we found that IDN5174 maintained the biological and antitumor properties, in spite of lack of the closed E ring. The available results support the interpretation that the polyamine linked at the 21-position may allow a favorable drug interaction in the ternary complex.

Pharmacokinetic measurements of IDN 5390 using electrospray ionization tandem mass spectrometry: structure characterization and quantification in dog plasma.

In this report, electrospray ionization tandem mass spectrometry (ESI-MS/MS) for a pharmacokinetic study of IDN 5390, a novel C-seco taxane derivative, which is under preclinical evaluation, has been investigated. Our results showed that IDN 5390 and other taxanes including paclitaxel and IDN 5109 could ionize well in not only positive-, but also in negative-ion mode. Under collision-induced dissociation (CID) conditions, these compounds could fragment into similar M- (molecular), T- (taxane ring) and S- (side chain) series ions. In positive-ion ESI, the formation of both T- and S-series ions involved the breaking of the C-13 ester bond. In negative-ion ESI, however, while the formation mechanism of S-series ions remained the same, the breaking of the C-1' carboxylic ester bond resulted in T-series ions. At optimum collision energy (CE) values, M-, T- and S-series ions of IDN 5390 in both positive- and negative-ion ESI-MS/MS spectra had good intensity. This phenomenon makes both positive- and negative-ion ESI-MS/MS good methods for IDN 5390 metabolite structural characterization, i.e. to reveal the location of modification groups in IDN 5390 metabolites versus IDN 5390 either on the side chain or the taxane ring. A liquid chromatography (LC)/ESI-MS/MS method using the multiple-reaction monitoring (MRM) technique was thereafter developed to quantify IDN 5390 in dog plasma using paclitaxel as internal standard. The method was validated using a concentration range between 5 and 1000 ng/mL and had a limit of detection of 1 ng/mL. The inter-day %CV (%coefficient of variation) of the calibration standards ranged between 4.36 and 9.64%, the intra-day %CV of the calibration standards between 0.61 and 13.44%, and the mean % accuracy of the quality control samples at the low, middle and high end of the concentration curves were 12.5, 6.8 and 9.6%, respectively.