Cholesterol content in tumor tissues is inversely associated with high-density lipoprotein cholesterol in serum in patients with gastrointestinal cancer.
BACKGROUND
The authors have previously demonstrated in different experimental models that sustained processes of cellular growth are characterized by alterations of cholesterol metabolism not only in the proliferating tissues but also in the plasma compartment.


METHODS
To evaluate whether alterations of cholesterol metabolism similar to those observed in experimental models are also associated with human cancer, in the present study cholesterol distribution in tumor tissues and lipid composition in the plasma compartment were determined in patients with different types of gastrointestinal cancer.


RESULTS
The results showed that tumor tissues contain increased amounts of cholesterol when compared with the corresponding normal tissues. Intracellular alterations of cholesterol were accompanied by specific changes of cholesterol in the plasma compartment: high-density lipoprotein (HDL) cholesterol was markedly reduced in the serum of patients with gastrointestinal cancer and the lipoprotein profiles showed a decrease in HDL3 fraction, the main HDL subfraction in human serum. The decrease of HDL cholesterol was negatively associated with the clinical stage of the disease. No changes in either total or low-density lipoprotein cholesterol levels were observed.


CONCLUSIONS
A major function attributed to HDL is to maintain normal cell cholesterol homeostasis by removing excess of cholesterol from intracellular pools. Because the use and storage of cholesterol are increased within the tumor tissues during growth, it is possible to hypothesize that low HDL levels observed in patients with gastrointestinal cancer are associated with the increased cholesterol metabolism in proliferating tissues.
Dessì
S
S
Istituto di Patologia Sperimentale, Cagliari, Italy.
Batetta
B
B
Pulisci
D
D
Spano
O
O
Anchisi
C
C
Tessitore
L
L
Costelli
P
P
Baccino
F M
FM
Aroasio
E
E
Pani
P
P
D000328:Adult; D000368:Aged; D002784:Cholesterol / Q000097:blood / Q000378:metabolism*; D008076:Cholesterol, HDL / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood; D005770:Gastrointestinal Neoplasms / Q000097:blood / Q000378:metabolism* / Q000473:pathology; D006706:Homeostasis; D006801:Humans; D008875:Middle Aged; D009367:Neoplasm Staging; D014018:Tissue Distribution
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D002784:Cholesterol