Colorimetric heparinase assay for alternative anti-metastatic activity.

Heparanase has been previously associated with the metastatic potential, inflammation, and angiogenesis of tumor cells. Heparanase activity has been detected by means of UV absorption, radiolabeled substrates, electrophoretic migration, and heparan sulfate affinity assays. However, those methods have proven to be somewhat problematic with regards to application to actual biological samples, the accessibility of the immobilized substrates, experimental sensitivity, and the separation of degraded products. Rather than focusing on heparanase activity, then, we have developed a rapid, alternative colorimetric heparinase assay, on the basis of the recent finding that sulfated disaccharides generated from heparin by bacterial heparinase exhibit biological properties comparable to those from heparan sulfate by mammalian heparanase. In this study, the concentrations of porcine heparin and bacterial heparinase I were determined using a Sigma Diagnostics Kit. Morus alba was selected as a candidate through this assay system, and an inhibitor, resveratrol, was purified from its methanol extract. Its anti-metastatic effects on the pulmonary metastasis of murine B16 melanoma cells were also evaluated. Our findings suggest that this assay may prove useful as a diagnostic tool for heparinase inhibition, as an alternative anti-metastatic target.

Activity of the herbal combination, PC-SPES, in the treatment of patients with androgen-independent prostate cancer.

OBJECTIVES: To retrospectively evaluate the response to treatment with PC-SPES, an herbal supplement, because patients with androgen-independent prostate cancer have limited treatment options. METHODS: A retrospective analysis was performed of patients with prostate cancer progression despite androgen ablation therapy who were treated with PC-SPES (3 capsules twice daily). We explored potential predictors of response. RESULTS: Twenty-three patients with androgen-independent prostate cancer were treated. The median age was 70 years. Eighteen patients had received prior secondary hormonal treatment and 10 prior chemotherapy. With a median follow-up of 8 months, 20 (87%; 95% confidence interval 66% to 97%) of 23 patients experienced a post-therapy decline in prostate-specific antigen (PSA). The median decline in PSA among these patients was 40% (range 1% to 88%). Of 23 patients, 12 (52%; 95% confidence interval 31% to 73%) had a greater than 50% decline in PSA. The median duration of the PSA response was 2.5 months (range 1 to 9+); the median time from the start of therapy to PSA progression was 6 months (range 2 to 12). Seven patients died of progressive prostate cancer. Toxicity was mild and included nipple tenderness, nausea, and diarrhea. One patient with a known history of coronary artery disease developed angina. In univariate analyses, older patients and those with a longer duration of initial androgen ablation therapy were more likely to respond to PC-SPES. CONCLUSIONS: PC-SPES is a well-tolerated and active treatment for androgen-independent prostate cancer. Additional testing is necessary to identify the active components of PC-SPES and its role in the treatment of patients with androgen-independent prostate cancer.

Phospholipase Cgamma1 inhibitory principles from the sarcotestas of Ginkgo biloba.

Ten phenolic compounds were isolated from the CHCl3 extract of Ginkgo biloba sarcotestas (Ginkgoaceae) as a new class of phosphatidylinositol-specific phospholipase Cgamma1 (PI-PLCgamma1) inhibitors. The substances without the long chain were ineffective. On the other hand, the activities of these compounds were dramatically decreased by acetylation of aromatic hydroxyl groups of cardanol, phenolic acid, and bilobol and by methylation of the aromatic carboxyl group of phenolic acid. The unsaturated long chain as well as the aromatic hydroxyl and carboxyl groups might play a key role for the PI-PLCgamma1 inhibitory activity. These compounds also inhibited the growth of a number of human cancer cell lines, but were less cytotoxic against a human normal colon cell line.

Inhibition of phospholipase C gamma 1 by the prenylated flavonoids from Sophora flavescens.

The effect on the phospholipase C gamma 1 activity of eleven prenylated flavonoids from Sophora flavescens was investigated. These flavonoids exhibited relatively strong inhibitory activity with IC50 values ranged from 7.5 x 10(-6) M to 35 x 10(-5) M with the exception of kushenol H (4) (IC50 value; > 5.3 x 10(-4) M). The presence of C3-OH resulted in a significant diminution of activity and the configuration of C3-OH is likely to be another factor influencing the activity. In addition, hydration of the C-4"'-C-5"' double bond of the lavandulyl side chain caused complete loss of activity. These data suggest that the presence and configuration of C3-OH are related to the inhibitory activity and the lavandulyl side chain is also important for high inhibitory activity against PLC gamma 1.

Inhibition of phospholipase C gamma 1 activity by amentoflavone isolated from Selaginella tamariscina.

Amentoflavone was isolated as an inhibitor of phospholipase C gamma 1 (PLC gamma 1) and phosphoinositides (PI)-turnover in PLC gamma 1 overexpressing NIH3T3 fibroblasts (NIH3T3 gamma 1) from Selaginella tamariscina (Selaginellaceae) together with other related biflavonoids, isocryptomerin and cryptomerin B. Only amentoflavone inhibited the PLC gamma 1 activity with an IC50 of 29 microM and the formation of total inositol phosphates (IPt) in PDGF-stimulated NIH3T3 gamma 1 with an IC50 of 9.2 microM but did not show inhibitor activity against protein kinase C. Isocryptomerin and cryptomerin B did not show inhibitor activity against PLC gamma 1 at the concentration of 150 microM, and did not inhibit IPt production in PDGF-induced NIH3T3 gamma 1 at the concentration of 180 microM.