Increased GS-II lectin binding and SATB2 downregulation are biological features for sessile serrated lesions and microvesicular hyperplastic polyps.

Sessile serrated lesions (SSLs) and microvesicular hyperplastic polyps (MVHPs) are colorectal lesions displaying gastric differentiation. Griffonia simplicifolia-II (GS-II) is a lectin specific to terminal α/ßGlcNAc residues. Here, we assessed GS-II binding and performed immunostaining for HIK1083 (specific to terminal αGlcNAc residues), MUC5AC, MUC6, and special AT-rich sequence binding protein 2 (SATB2) in SSLs, MVHPs, and tubular adenomas (TAs). We observed MUC5AC positivity in 28 of 30 SSLs, but in only three of 23 TAs. Moreover, 24 of 30 SSLs were MUC6-positive, while none of the 23 TAs were MUC6-positive. None of the 30 SSLs or 23 TAs showed HIK1083 positivity. All 30 SSLs and 26 MVHPs were GS-II-positive, while only seven of 23 were in TAs. GS-II staining was mainly distributed in the Golgi region, but SSLs and MVHPs showed goblet cell distribution, in 20 of 30 and 19 of 26 cases, respectively. All SSLs, MVHPs, and TAs were SATB2-positive, but 21 of 30 SSLs and 12 of 26 MVHPs showed decreased staining intensity relative to adjacent mucosa, a decrease seen in only two of 23 in TAs. These results indicate overall that increased terminal ßGlcNAc and decreased SATB2 expression are characteristics of SSLs and MVHPs.

A new ß-carboline alkaloid from the seeds of Griffonia simplicifolia.

AIM: To study the chemical constituents from the seeds of Griffonia simplicifolia Baill. METHODS: The chemical constituents were isolated and purified by a combination of chromatographic materials including silica gel, Sephadex LH-20, and preparative TLC. Their structures were elucidated on the basis of MS and NMR data analysis. The cytotoxic activities were evaluated against HepG2 cancer cell line using the MTT colorimetric method. RESULTS: A new ß-carboline alkaloid, griffonine (1), together with seven known alkaloids, hyrtioerectine B (2), 3-carboxy-6-hydroxy-ß-carboline (3), hyrtiosulawesine (4), 5-hydroxyindole-3-carbaldehyde (5), 5-hydroxy-3-(2-hydroxyethyl) indole (6), trigonelline (7), and 5-hydroxytryptamine (8) were isolated and identified. Alkaloids 1, 2 and 4 showed growth inhibitory effects on the HepG2 cell line with IC50 values of 23.5, 9.6 and 19.3 µmol·L(-1), respectively. CONCLUSION: Alkaloid 1 is new and was named griffonine. Alkaloids 2-7 were isolated from this plant for the first time. Alkaloids 1, 2 and 4 were potentially cytotoxic.

Regulation of CD1, Ki-67, PCNA mRNA expression, and Akt activation in estrogen-responsive human breast adenocarcinoma cell line, MCF-7 cells, by griffonianone C, an isoflavone derived from Millettia griffoniana.

CONTEXT: Millettia griffoniana Baill. (Fabaceae), which contains isoflavonoids like griffonianone C (Griff C), is commonly used in the folk medicine in Cameroon to treat various ailments. Possible health benefits of Griff C which include alleviation of menopausal symptoms, limitation of bone resorption, and lowering of the risks of cancer and cardiovascular diseases attracted our interest. OBJECTIVE: The effects of Griff C on the regulation of the expression of proliferation markers such as proliferating cell nuclear antigen (PCNA), cyclin D1 (CD1) and Ki-67 are investigated here. Its role in apoptosis or cell survival, through the phosphatidylinositol 3 kinase-Akt (PI3K-Akt) signaling pathway is further studied. MATERIALS AND METHODS: Semiquantitative real-time PCR was performed to analyze the effects of Griff C on gene expression in MCF-7 cells. Western blot analysis was used to assess the role of Griff C on the expression of phosphorylated Akt in MCF-7 cells. RESULTS: Griff C induced a 4.84-fold increase in the expression of Ki-67 mRNA at the concentration of 10(-8) M and a 3.90-fold increase of CD1 mRNA at 10(-7) M. Griff C slightly increased the phosphorylation of Akt at its serine 473 residue. Akt phosphorylation was inhibited by the PI3K inhibitor, LY294002, but not by the specific estrogen receptor antagonist, fulvestrant. DISCUSSION AND CONCLUSION: These findings suggest that Griff C can modulate proliferation of MCF-7 cells. Our results also suggest that Griff C can affect the PI3K-related signaling pathway. Thus, Griff C may exert part of its low proliferative and antiapoptotic effects by a nongenomic mode of action.

O-glycosylation expression in fibroadenoma.

Fibroadenomas are human benign breast tumors characterized by proliferation of epithelial and stroma cells of the terminal ductal unit. Expression of O-glycans seems to contribute to the proliferation and transformation events. With this in mind, we evaluated the expression of glycans in fibroadenoma tissue through immunohistochemistry with antibodies against mucin epitopes (Anti CA15-3 and MUC1), as well as with lectins specific for glycans linked to proteins or lipids, and we compared findings with healthy breast specimens. Our results show positive expression of CA15-3 and MUC1 in fibroadenoma tissue, mainly in duct and stroma cells, whereas, in normal samples, staining was observed in duct cells. The lectin from Glycine max recognized equally well duct and stroma cells; this was the only lectin showing co-localization with anti-CA15-3 in healthy and tumor tissues. Dolichos biflorus, Artocarpus integrifolia, and Griffonia simplicifolia lectins recognized duct cells in control healthy tissues as well as in fibroadenoma tissue. The lectin from Amaranthus leucocarpus recognized only duct cells in control samples, whereas, in fibroadenoma tissue, it recognized duct and some stromal cells, suggesting that O-glycans-type mucin linked to proteins and mucin participate in the development of fibroadenomas.

Use of amaranthus leucocarpus lectin to differentiate cervical dysplasia (CIN).

Alterations in O-glycosylation of proteins in cell surfaces can originate disorder in cellular function, as well as in cell transformation and tumoral differentiation. In this work, we investigate changes in O-glycosylation in cervical intraepithelial dysplasia (CIN) at different stages of differentiation (CIN I, CIN II, and CIN III) using lectins specific for O-glycosidically linked glycans. Twenty cases with CIN I, CIN II, and CIN III dysplasias each, and 20 normal cases were studied by lectin histochemistry and evaluated under optical microscopy. The lectins from Glycine max and Griffonia simplicifolia showed no differences in their recognition pattern among the different CIN stages and normal tissue. Dolichos Biflorus lectin recognized CIN I dysplasia. Lectin from Amaranthus leucocarpus showed increased reactivity in the presence of CIN II dysplasia, compared with CIN I and CIN III. These results suggest that subtle modifications in the O-glycosylation pattern could be considered in diagnosis or prognosis of cervical precancerous stages.

Comparison of the binding properties of the mushroom Marasmius oreades lectin and Griffonia simplicifolia I-B isolectin to alphagalactosyl carbohydrate antigens in the surface phase.

The binding of two alpha-galactophilic lectins, Marasmius oreades agglutinin (MOA), and Griffonia simplicifolia I isolectin B(4) (GS I-B(4)) to neoglycoproteins and natural glycoproteins were compared in a surface phase assay. Neoglycoproteins carrying various alpha-galactosylated glycans and laminin from basement membrane of mouse sarcoma that contains the xenogenic Galalpha1-3Gal1-4GlcNAc epitope were immobilized in microtiter plate wells and lectin binding determined with an enzyme-linked assay. After 24 h of incubation, MOA had higher affinity for the xenogenic pentasaccharide (Galalpha1-3Gal1-4GlcNAcbeta1-3Galbeta1-4Glc) than for the Galalpha-monosaccharide. The binding properties of MOA and GS I-B(4) to the xenogenic disaccharide (Galalpha1-3Galbeta1) were comparable while the binding of MOA to the xenogenic pentasaccharide was much stronger than the binding of GS I-B(4) to the same epitope. Non-xenogenic disaccharide-coupled neoglycoproteins having galactose end groups linked alpha1-2 or alpha1-4 to Gal or linked alpha1-3 to GalNAc bound very weakly to MOA, whereas GS I-B(4) recognized all of these disaccharides with similarly high affinity. MOA also showed high affinity for laminin. The results indicate that the Marasmius oreades lectin has nearly the same affinities as does GS I-B(4) for the simple xenogenic carbohydrate antigens, but MOA has greater affinity for the pentasaccharide and is far more specific in its binding preferences than the Griffonia lectin.

Maturity of pericytes in cerebral neocapillaries induced by growth factors: fluorescence immuno-histochemical analysis using confocal laser microscopy.

The maturity of pericytes in cerebral neocapillaries induced by two different growth factors: basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF), was examined using an immunohistochemical staining technique. Cerebral angiogenesis was induced in mice by implanting a sandwich system of bFGF/PDGF gel and nylon-mesh over the exposed cortex. On 28th day after incubation, a small volume of cerebral tissue with the nylon-mesh was isolated and stained using tetramethyl rhodamine isothiocyanate (TRITC)-labeled secondary antibody to the primary antibody against NG_2 proteoglycan and fluorescein isothiocyanate (FITC)-labeled Griffonia simplicifolia (GS)-lectin. Using a confocal laser microscopic system, we observed the cerebral neocapillaries on the upper surface of the nylon-mesh and evaluated the maturity of pericytes stained with NG_2 based on the fluorescence immunohistological images. The pericyte appeared rich in neocapillaries induced by PDGF. It was suggested that pericytes might play a key role in the regulation of blood flow in neovessels.