Liver cancer is a growing global health challenge, with an estimated annual incidence of
>1 million cases worldwide by 2025.
Hepatocellular carcinoma (HCC) accounts for approximately 90% of the cases of liver
cancer and is associated with high morbidity and mortality.
The most prominent risk factors for HCC include hepatitis B (HBV), hepatitis C (HCV)
viral infections and non-alcoholic steatohepatitis (NASH), which can lead to liver
fibrosis and cirrhosis.
Other risk factors include heavy alcohol consumption, non-alcoholic fatty liver disease
(NAFLD), consumption of aflatoxins, obesity associated with metabolic syndrome, type 2
diabetes (T2D), and tobacco smoking.
Sialic acids (SAs) are a subset of nine carbon acidic sugars that contain approximately
fifty derivatives of neuraminic acids. The most common sialic acid derivatives found in
mammals are N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc).
Sialic acid (SA) structural diversity leads to many biological functions, including
antiviral activity, antioxidant activity, anti-adhesion activity , anti-inflammatory
property, and improving learning and memory, promoting bone growth and prebiotics .
SA can participate in important pathological and physiological processes and can be used
as nutrition, drugs and drug carriers to prevent diseases. Therefore, SA is a promising
active substance, which can improve human health.
SAs on tumor cell surfaces are aberrantly expressed during tumor transformation and
malignant progression. In general, hypersialylation is frequently observed in tumor
tissues compared to corresponding normal tissue.
The increased SAs in tumor cells are mainly caused by the special metabolic flux and
aberrant expression of sialyltransferases/sialidases.
Abnormal expression of SA is atypical symbol of tumor cells. β-galactoside α2,6 sialyl
transferases is closely related to tumorigenesis and tumor progression. High levels of
β-galactoside α2,6-sialyltransferases mediated tumorigenesis and metastasis in HCC cells
by activating the Wnt/β-catenin pathway.
The high sensitivity of SAs in serum or plasma as a tumor marker has been reported in
various cancerous conditions. Quantification of total SAs or glycolipid-bound sialic
acids in serum is helpful to improve the accuracy of clinical diagnoses and therapies.
The level of SA activity was found to offer highly specific and sensitive tumor biomarker
for HCC diagnosis and follow up of HCC post-therapy.