RESUMO
BACKGROUND: Gypsophila trichotoma Wend. (Caryophyllaceae) is a medicinal plant which is protected in Bulgaria by the Biodiversity Law. Previous studies have showed the presence of triterpene saponins, sterols, flavonoids, triterpens, etc. OBJECTIVE: Gypsogenic acid, isolated from Gypsophila trichotoma roots, was evaluated for cytotoxic activity. MATERIALS AND METHODS: The structure of the compound was elucidated by spectral methods. The cell survival fraction was determined by the MTT dye reduction assay, performed with some modifications. RESULTS: Gypsogenic acid was tested in a panel of human tumor cell lines and was found to inhibit the proliferation of malignant cells. It was active against leukemic cells with lymphoid (SKW-3 and BV-173) or myeloid phenotype (HL-60, K-562, and LAMA-84), as well as against the EJ bladder carcinoma cell line. Bcr-Abl expressing myeloid cells (LAMA-84 and especially K-562) displayed lower sensitivity. HL-60/Dox cells were less sensitive to gypsogenic acid than the parent cell line, which shows that gypsogenic acid is probably a substrate of MRP-1.
RESUMO
A total of 50 patients with chronic lymphocytic leukaemia (CLL), as well as the B-cell leukaemia cell lines MEC-1, JVM-3, and BV-173 were studied in order to assess the incidence of CD13/aminopeptidase N (APN) immunolabelling with a monoclonal antibody 7H5 compared to LeuM7 and to CD13 mRNA levels, and to correlate these data with the cytotoxic and apoptosis-induction activity of the natural phenolic APN inhibitor curcumin. CD13/APN was detected in a significant proportion of B-CLL patients (42/50, 84%), immunolabelled by 7H5 (42/50) ± LeuM7 (10/50). Molecular analysis for CD13 transcripts confirmed these data, resulting in a specific RT-PCR product in CD13 positive cases. Curcumin showed concentration-dependent cytoreductive efficacy and apoptosis-induction activity in all tested cell lines and primary cultures from CLL mononuclear cells. There was a clear tendency for a better response in CD13 positive cases. The incidence of CD13/APN in CLL suggests that the inhibition of APN/CD13 by curcumin may be an effective new molecular target for a more efficient therapy for these patients and warrants further investigations.