Production and Role of Hormones During Interaction of Species With Maize ( L.) Seedlings.

It has long been known that hormones affect the interaction of a phytopathogen with its host plant. The pathogen can cause changes in plant hormone homeostasis directly by affecting biosynthesis or metabolism in the plant or by synthesizing and secreting the hormone itself. We previously demonstrated that pathogenic fungi of the species complex are able to produce three major types of hormones: auxins, cytokinins, and gibberellins.

Mechanisms of natural brassinosteroid-induced apoptosis of prostate cancer cells.

Brassinosteroids (BRs) are a group of polyhydroxylated sterol derivatives with important regulatory roles in various plant physiological processes. The aim of this study was to examine the mechanism of the antiproliferative activity of natural BRs 28-homocastasterone (28-homoCS) and 24-epibrassinolide (24-epiBL) in hormone-sensitive and -insensitive (LNCaP and DU-145, respectively) human prostate cancer cell lines. The effects of BRs on prostate cancer cells were surveyed using flow cytometry, Western blotting, TUNEL, DNA ladder assays and immunofluorescence analyses.

Synthesis and biological activity of 22-deoxo-23-oxa analogues of saponin OSW-1.

Analogues of the potent cytotoxic saponin OSW-1 were prepared from the readily available steroidal 16β,17α,22-triol. The new 22-deoxo-23-oxa analogues of OSW-1 were screened against eight cancer cell lines and normal human fibroblasts. The analogues proved to be slightly less active than OSW-1 but also less toxic to normal cells.