Send to:

Choose Destination
See comment in PubMed Commons below
Biochem Biophys Res Commun. 1996 Aug 14;225(2):617-20.

The immune stimulatory protein 90K increases major histocompatibility complex class I expression in a human breast cancer cell line.

Author information

  • 1Department of Medical Oncology, University G. D'Annunzio Medical School, Chieti, Italy.


90K is a widely expressed, secreted 90 kDa human serum protein found both in normal individuals and at elevated levels in the serum of cancer patients. Functional characterization revealed stimulatory effects of 90K on immune defense systems, such as natural killer and lymphokine-activated killer cell activity. Recently, experiments have shown that 90K expression in several tumor cell lines inversely correlates with tumor formation in athymic mice. The mechanism of this tumor suppressive effect is unknown. In the present study, we evaluated the ability of 90K to affect the expression of MHC class I molecules in the human breast cancer cell line EVSA-T. Treatment with 90K (1-50 micrograms/ml) caused the levels of MHC class I expression to increase approximately sixfold above control levels, as measured by flow cytometry. IFN-gamma was used as a positive control and yielded increased expression of MHC class I molecules approximately 8 times over control levels. These data demonstrate that 90K can directly affect the expression of molecules that are engaged in protective antitumor response.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk