The Utility of Lipid-Associated Sialic Acid (LASA or LSA) as a Serum Marker for Malignancy

Abstract

The utility of the lipid-associated sialic acid (LASA or LSA) test as a serum marker for malignancy is reviewed. The name LASA or LSA test is confusing because it suggests that only or mainly lipid-bound sialic acid is measured. In reality, glyco-protein-bound sialic acid is determined predominantly. The assay appears to have a particularly high positivity rate in leukemia, Hodgkin’s disease, melanoma, sarcoma, advanced ovarian carcinoma and oropharyngeal tumors, suggesting that LASA may serve as a valuable marker in these malignancies. As a consequence of the rise of sialic acid-rich acute-phase proteins, such as αi-acid glycoprotein, in inflammatory diseases the specificity of LASA and therefore its diagnostic accuracy is low. LASA can be useful for monitoring cancer patients during treatment, especially in combination with other tumor markers.

Evaluation of Serum Total Sialic Acid and Lipid Associated Sialic Acid as a Tumour Marker

“…(12) in this present study we found higher levels of LDH in non malignant diseases and there is no statistically significant difference between malignant and non malignant diseases. (16) decreased protein values in nonmalignant and there is no statistically significant difference in protein values in malignance and non-malignance. These findings indicate their non specificity.…”

Serum sialic acid fractions in Kangal breed bitches with transmissible venereal tumours

“…This causes excess amount of sialic acid penetration into the sera. Elevated serum TSA, and also LSA have been used to tumour markers for a number of different types of tumour, and explained by a spontaneous release (shedding) of aberrant sialic acid containing cell surface glycoconjugates (1,17). Measurement of these markers is simple, non-invasive, inexpensive and reproducible methods (35).…”

Interleukin-2 Binds to Ganglioside GD1b

“…Although GM 3 is the major ganglioside in circulation of healthy individual (26), other gangliosides such as GD 1b from tumor tissues enter into the circulation in cancer patients (3,10). The expression of GD 1b in melanoma biopsies suggests that it may bind to rIL-2 administered therapeutically.…”