concanavalin-a and Fibroadenoma

Fluorescent compounds have been widely used for biomolecule labeling in cytochemistry and histochemistry analysis. Here, it is described the optical properties of dimethyl 2-[(acridin-9-yl)methylidene]-malonate (LPSF/IP-81), an acridine derivative. This compound was conjugated to Concanavalin A (Con A) lectin and applied as sugar probe in lectin histochemistry. Evaluation of luminescent properties showed that LPSF/IP-81 is photoluminescent with excitation at 360 nm and emission at 428 nm. Con A hemagglutinating activity and LPSF/IP81 photoluminescence were unaltered after conjugation. Circular dichroism of Con A-LPSF/IP81 conjugate showed the maintenance of the Con A structure. Lectin histochemistry with Con A-LPSF/IP81 conjugate demonstrated different pattern recognition studying normal, fibroadenoma, and invasive ductal carcinoma of human breast. These findings indicate that LPSF/IP-81 can be proposed as an alternative probe for histochemical analysis.

Topics: Acridines; Breast; Breast Neoplasms; Carcinoma, Ductal, Breast; Circular Dichroism; Concanavalin A; Female; Fibroadenoma; Fluorescence; Fluorescent Dyes; Humans; Lectins; Malonates

Nowadays, there is an increase of investigations into the fibroadenoma, mainly because some studies have shown that the occurrence of fibroadenoma is linked to an increased risk of developing breast carcinoma. Currently, the chemiluminescence biomarkers are applied for validation methods and screening. Here, a lectin chemiluminescence is proposed as new histochemistry method to identify carbohydrates in mammary tumoral tissues. The lectins concanavalin A (Con A) and peanut agglutinin (PNA) conjugated to acridinium ester were used to characterize the glycocode of breast tissues: normal, fibroadenoma, and invasive duct carcinoma (IDC). The lectin chemiluminescence expressed in relative light units (RLU) was higher in fibroadenoma and IDC than in normal tissue for both lectins tested. The relationship RLU emission versus tissue area described a linear and hyperbolic curve for IDC and fibroadenoma, respectively, using Con A whereas hyperbolic curves for both transformed tissues using PNA. RLU was abolished by inhibiting the interaction between tissues and lectins using their specific carbohydrates: methyl-α-D: -mannoside (Con A) and galactose (PNA). The intrinsic fluorescence emission did not change with combination of the lectins (Con A/PNA) to the acridinium ester for hydrophobic residues. These results represent the lectin chemiluminescence as an alternative of histochemistry method for tumoral diagnosis in the breast.

Topics: Biomarkers; Breast Neoplasms; Carbohydrate Metabolism; Carbohydrates; Carcinoma, Ductal, Breast; Concanavalin A; Female; Fibroadenoma; Humans; Luminescent Measurements; Middle Aged; Peanut Agglutinin

The organotypic culture technique and quantitative gelatin zymography were used to determine the expression of matrix metalloproteinase (MMP)-9 and MMP-2 in human breast cancer and adjacent normal breast tissue and fibroadenoma. MMP-9 and MMP2 were constitutively expressed in all cultures. The release of these two enzymes in breast cancer was higher than that in adjacent normal breast tissue and fibroadenoma. Administration of 12-o-tetradecanoyl- phorbol-13-acetate (TPA) increased the release of MMP-9 but not of MMP-2. This response was inhibited by protein kinase C (PKC) inhibitor (H7), transcription inhibitor (actinomycin D) and translation inhibitor (cycloheximide). Moreover, the increased level of MMP-9 by TPA in breast cancer was also higher than that in adjacent normal breast tissue and fibroadenoma. These phenomena were also observed in the DAG-treated culture. These findings suggested that the MMP-9 expression in the breast cancer tissue may be more sensitive for the PKC activation.

Topics: 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; Breast; Breast Neoplasms; Concanavalin A; Cycloheximide; Dactinomycin; Enzyme Activation; Enzyme Activators; Female; Fibroadenoma; Gelatin; Humans; Matrix Metalloproteinase 9; Matrix Metalloproteinase Inhibitors; Organ Culture Techniques; Protease Inhibitors; Protein Biosynthesis; Protein Kinase C; Protein Synthesis Inhibitors; Transcription, Genetic