Soluble interleukin-2 receptor and soluble CD8 antigen levels in serum from patients with solid tumors.
High levels of soluble lymphocyte antigens have been described in a large number of tumors and, particularly, in hematopoietic neoplasms. As previously reported, many antitumor immune responses are IL-2 dependent: clinical observations indicate that a worse survival in advanced tumor patients is related with a decrease of soluble IL-2 levels. A soluble form of CD8 has been described: as found in Hodgkin's disease and acute lymphoblastic leukemia, sCD8 levels have a prognostic value. To explain the significance of these soluble molecules in solid tumors, we a) determinated sIL-2R and sCD8 in 84 patients; b) correlated the expression of p55 chain of IL-2R and CD8 antigen on the cell-surface of peripheral lymphocytes to sIL-2R and sCD8 levels; c) analyzed endogenous IL-2R levels in patients with lung cancer. An increase of sIL-2R was found in 82% of cases, while high levels of sCD8 were observed in 32%; no correlation was observed between sIL-2R and the expression of p55 on the surface of peripheral lymphocytes: IL-2 levels in patients with NSCLC were significatively reduced, when compared to healthy controls, with an inverse relationship between endogenous IL-2 concentration and sIL-2R levels. Whatever may be the physiopathological mechanism of the increase of sIL-2 observed in solid tumors, this rise may contribute to the immunodepression correlated to neoplastic disease. Therefore, higher levels of sIL-2R/IL-2 ratio has a negative biologic prognostic significance. We think that determinating CD8 antigen in the serum can offer a more sensitive and specific measurement of activation of suppressor/cytotoxic T-lymphocytes.
Orditura
M
M
Division of Medical Oncology, Department of Internal and Experimental Medicine, II University School of Medicine of Naples, Naples, Italy.
De Vita
F
F
Roscigno
A
A
Auriemma
A
A
Infusino
S
S
Catalano
G
G
D000328:Adult; D000368:Aged; D000951:Antigens, Neoplasm / Q000097:blood*; D000954:Antigens, Surface / Q000097:blood; D016827:CD8 Antigens / Q000097:blood*; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood* / Q000378:metabolism; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000097:blood* / Q000378:metabolism; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D015375:Receptors, Interleukin-2 / Q000097:blood*; D012995:Solubility
D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D016827:CD8 Antigens; D015375:Receptors, Interleukin-2