Elevated sialyltransferases (the enzymes responsible for the addition of sialic acid to growing glycoconjugate chains) and the resultant hypersialylation of tumor cell surfaces are biomarkers of several cancers, including lung, breast, ovarian, pancreatic, and prostate cancer. CD BioGlyco focuses on sialic acid research and provides clients with high-quality sialic acid analysis services in prostate cancer.
Prostate cancer is a malignant tumor that begins in the man reproductive system, which is becoming a great detriment to male health. Furthermore, prostate cancer is prone to bone metastases, and a considerable proportion of the patients are diagnosed at an advanced stage.
The roles of glycans in cancer have been highlighted by the fact that alterations in glycosylation could promote invasive behavior of tumor cells that ultimately lead to the progression of cancer. The abnormal glycosylation process in tumor cells increases the sialic acid level on the surface of malignant and transformed cells by contributing to the biosynthesis of carbohydrate structures. Sialic acid is a general term for a series of hydroxylated monosaccharide derivatives containing 9 carton atoms at the methylated non-reduction terminal of glycoproteins and glycolipids. The sialic acid level may be a promising diagnostic and prognostic biomarker for prostate cancer and bone metastases. We determine the concentration of serum sialic acid using the Roche Cobas 8000 automatic analyzer. Furthermore, the levels of serum sialic acid are also assessed using a colorimetric assay.
Fig.1 Glycosylation changes in prostate cancer progression. (Butler, 2021)
Sialic acids are present on both N- and O-linked glycans and usually attach to an underlying galactose residue via an α-(2,6) or α-(2,3)-glycosidic linkage. The α-(2,6)-sialylation is widely present in healthy tissues. Although α-(2,3)-linked sialic acid is rarely found in healthy tissues but is greatly elevated in cancer. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) is used with a focus on the analysis of sialic acid linkages. The expression of Sialyl Lewis x Antigen (a tetrasaccharide containing an α-(2,3)-terminal sialic acid and α-(1,3)-fucose) is associated with metastatic spread of cancer with a significantly poorer patient’s prognosis in prostate cancer.
The best-known marker for prostate cancer is prostate-specific antigen (PSA). An electrochemical lectin-based immunosensor is applied both for detection of PSA concentration and profiling of PSA’s glycan, which composition varies with prostate cancer development/progression. The quantitative measurement of serum PSA is carried out using an immunoenzymetric in vitro assay.
Analysis of altered protein glycosylation is gaining increased attention. Lectin Microarrays have distinct advantages such as a possibility for extremely high throughput of analysis, low sample/reagent consumption with high reliability of assays. For example, lectins (natural glycan recognizing proteins) detect glycans still attached to intact proteins or cells in natural conformation. Moreover, lectins recognize different linkages between two carbohydrates within a glycan structure (i.e. α-(2,3)-linked vs. α-(2,6)-linked sialic acid to galactose), which is quite difficult for an instrumental-based approach.
CD BioGlyco has developed a label- and reagent-free electrochemical method based on chronopotentiometric stripping analysis and a hanging mercury drop electrode for the detection of interaction of sialylated protein biomarker a PSA with two important lectins: Sambucus nigra agglutinin (SNA) and Maackia amurensis agglutinin (MAA).
CD BioGlyco has developed comprehensive sialic acid analysis solutions to help clients solve various problems encountered in the sialic acid analysis of prostate cancer. If you are interested in our services, please feel free to contact us.
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