cyanine-dye-3 and Neoplasm-Metastasis

The breast cancer metastasis suppressor 1 (BRMS1) gene has been shown to suppress metastasis without affecting the growth of the primary tumor in mouse models. It has also been shown to suppress the metastasis of tumors derived from breast, melanoma, and, more recently, ovarian carcinoma (see ref 1). However, how BRMS1 exerts its metastasis suppressor function remains unknown. To shed light into its metastatic mechanism of action, the sensitive 2D-DIGE analysis coupled with MS has been used to identify proteins differentially expressed by either overexpressing (Mel-BRMS1) or silencing BRMS1 (sh635) in a melanoma cell line. After comparison of the protein profiles from WT, Mel-BRMS1, and sh635 cells, 79 spots were found to be differentially expressed. Mass spectrometry analysis allowed the unambiguous identification of 55 polypeptides, corresponding to 43 different proteins. Interestingly, more than 75% of the identified proteins were down-regulated in Mel-BRMS1 cells compared to WT. In contrast, all the identified proteins in sh635 cells extracts were up-regulated compared to WT. Most of the deregulated proteins are involved in cell growth/maintenance and signal transduction among other cell processes. Six differentially expressed proteins (Hsp27, Alpha1 protease inhibitor, Cofilin1, Cathepsin D, Bone morphogenetic protein receptor2, and Annexin2) were confirmed by immunoblot and functional assays. Excellent correlation was found between DIGE analysis and immunoblot results, indicating the reliability of the analysis. Available evidence on the reported functions of the identified proteins supports the emerging role of BRMS1 as negative regulator of the metastasis development. This work opens an avenue for the molecular mechanisms' characterization of metastasis suppressor genes with the aim to understand their roles.

Topics: Bone Morphogenetic Protein Receptors, Type II; Carbocyanines; Cathepsin D; Cell Line; Cell Line, Tumor; Data Interpretation, Statistical; Electrophoresis, Gel, Two-Dimensional; Fluorescent Dyes; Humans; Melanoma; Neoplasm Metastasis; Neoplasm Proteins; Proteome; Proteomics; Repressor Proteins; RNA Interference; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

To elucidate the significance of beta-1,4-galactosyltransferase IV (beta-1,4-GT-IV) in the clinical presentation and prognostication of colorectal cancer.. Tissue lysates from paired tumor and nontumor tissues of a colon cancer patient were labeled separately with fluorescent dyes Cy5 and Cy3 for two-dimensional difference in-gel electrophoresis. Subsequent matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and immunoblot analyses identified a down-regulated level of beta-1,4-GT-IV in the tumor tissue. In the follow-up study, paired tissue lysates were obtained from 100 colorectal cancer patients with immunoblot analyses done to compare the levels of beta-1,4-GT-IV expression in these patients.. Of 100 colorectal patients studied, 48% had down-regulated expression of beta-1,4-GT-IV in the tumor tissue but 28% of patients exhibited elevated beta-1,4-GT-IV levels. Increased beta-1,4-GT-IV in the tumor tissue was significantly coexistent with raised serum level of CA-199 and the presence of tumor metastasis (P=0.006 and P<0.001, respectively) but was independent of age and gender of patient, tumor site, tumor size, serum level of carcinoembryonic antigen, grade of tumor cell differentiation, and depth of tumor invasion. The results of logistic regression analyses suggested that tumor beta-1,4-GT-IV overexpression and tumor invasion, but not other patient variables such as tumor size and serum levels of carcinoembryonic antigen and CA19-9, were significantly correlated with the occurrence of metastases (P<0.05). In a multivariate regression analysis, the patient group with tumor beta-1,4-GT-IV overexpression strongly predicted for tumor metastasis (odds ratio, 10.009; 95% confidence interval, 2.992-33.484; P<0.001). Likewise, tumor beta-1,4-GT-IV overexpression was significantly associated with poor overall survival (P<0.01). By Cox regression analysis, this association remained significant even after adjustment for tumor metastasis (P=0.048).. Increased beta-1,4-GT-IV expression in tumor tissue was strongly associated with tumor metastases and poor prognosis in colorectal cancer.

Topics: Aged; Carbocyanines; Colorectal Neoplasms; Electrophoresis, Gel, Two-Dimensional; Female; Galactosyltransferases; Humans; Male; Middle Aged; Neoplasm Metastasis; Prognosis; Risk Factors; Up-Regulation