Plasma sialyltransferase as a tumor marker.

Area of Science:

• Biochemistry
• Oncology
• Clinical Chemistry

Background:

• Neoplastic transformations alter cell membrane glycoproteins.
• Plasma sialyltransferase (ST) is crucial for adding sialic acid residues to cell surface glycoproteins.
• Elevated ST may correlate with cancer development.

Purpose of the Study:

• To measure plasma ST levels in normal individuals and cancer patients.
• To investigate the correlation between plasma ST and cancer type, age, and tumor burden.
• To assess the utility of plasma ST as a cancer biomarker.

Main Methods:

• Radiometric assay using (14C) CMP sialic acid to measure ST activity.
• Assay performed on plasma samples from 127 normal volunteers and 91 cancer patients.
• Serial determinations conducted in a subset of patients to correlate with tumor burden.

Main Results:

• Mean plasma ST was 837 units in normal volunteers.
• Significantly elevated mean plasma ST observed across multiple cancer types (e.g., breast, lung, colon).
• Plasma ST levels in treated breast cancer patients (757 units) approached normal levels; serial measurements correlated with tumor burden in most cases.

Conclusions:

• Plasma sialyltransferase is significantly elevated in patients with various cancers.
• Plasma ST determination shows potential as a biomarker for cancer monitoring and follow-up.
• Further research is warranted to establish ST as a reliable diagnostic and prognostic tool.