ABSTRACT
By means of liquid chromatography-electrospray ionization (LC-ESI) mass spectrometry two glucosinolates, glucoiberin and 3-hydroxy,4(α-L-rhamnopyranosyloxy) benzyl glucosinolate, were identified in the aqueous extract of Brassica oleraceae L var. italica. Further, two compounds were isolated after enzymatic hydrolysis of the aqueous extract by myrosinase, one of them was identified as 4-vinyl-3-pyrazolidinone. The second compound (sulphoraphane) 1-isothiocyanate-4-methyl-sulphinyl butane, converted to the most stable form of thiourea (sulphoraphane thiourea). The crude extract (80% alcohol extract) of broccoli florets was examined for cytotoxic activity against different human cancer cell lines, it showed good inhibition of colon cancer (IC(50) 3.88 µg/mL). On the other hand each of the successive extracts (petroleum ether, chloroform, ethyl acetate and ethanol) showed no significant cytotoxic activity. When myrosinase hydrolysate was tested for cytotoxic activity on the colon cancer cell line it showed very high activity - 95% lethality up to 0.78 µg/mL.
Subject(s)
Antineoplastic Agents/pharmacology , Brassica/chemistry , Glucosinolates/chemistry , Isothiocyanates/pharmacology , Plant Extracts/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Cell Line, Tumor , Cell Survival/drug effects , Chromatography, Liquid , Colonic Neoplasms/drug therapy , Flowers/chemistry , Glucosinolates/isolation & purification , Glycoside Hydrolases/metabolism , Humans , Hydrolysis , Inhibitory Concentration 50 , Isothiocyanates/chemistry , Isothiocyanates/isolation & purification , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Pyrazolones/chemistry , Pyrazolones/isolation & purification , Spectrometry, Mass, Electrospray Ionization , Sulfoxides , Thiourea/chemistry , Thiourea/isolation & purificationABSTRACT
INTRODUCTION: Epithelial-to-mesenchymal transition (EMT) is a process of molecular and phenotypic epithelial cell alteration promoting invasiveness. Loss of E-cadherin (E-CAD), a transmembrane protein involved in cell adhesion, is a marker of EMT. Proteolysis into N- and C-terminus fragments by ADAM10 and presenilin-1 (PSEN-1) generates soluble (sE-CAD) and transcriptionally active forms. We studied the protein expression patterns of E-CAD in the serum and placenta of women with histologically-confirmed over-invasive placentation. METHODS: The patterns of expression and levels of sE-CAD were analyzed by Western blot, immunoassay, and immunoprecipitation. Tissue immunostaining for E-CAD, cytokeratin-7 (epithelial marker), vimentin (mesenchymal marker), ADAM10, PSEN-1 and ß-catenin expression were investigated in parallel. RESULTS: N-terminus cleaved 80 kDa sE-CAD fragments were present in serum of pregnant women with gestational age regulation of the circulatory levels. Women with advanced trophoblast invasion did not display circulatory levels of sE-CAD different from those of women with normal placentation. Histologically, extravillous trophoblasts (EVT) closer to the placental-myometrial interface demonstrated less E-CAD staining than those found deeper in the myometrium. These cells expressed both vimentin and cytokeratin, an additional feature of EMT. EVT of placentas with advanced invasion displayed intracellular E-CAD C-terminus immunoreactivity predominating over that of the extracellular N-terminus, a pattern consistent with preferential PSEN-1 processing. DISCUSSION: Local processing of E-CAD may be an important molecular mechanism controlling the invasive phenotype of accreta EVT.