ABSTRACT
Sodium phenylacetate can induce differentiation of tumor cells and has been approved as a drug for the treatment of adults with cancer. In order to explore the immunological mechanism of its antitumor effect, the influence of sodium phenylacetate on HLA class I and II molecule expression in various human tumor cell lines, including breast adenocarcinoma (MCF-7.MUA-453), gastrocarcinoma(MKN-28,MKN-45), ovarian cancer(3AO) and cervical cancer(Hela), was studied with ELISA. The result showed that HLA class II molecule was absent from the surface of MCF-7 cells, but they could be induced after 7 days of continued treatment with sodium phenylacetate. Sodium phenylacetate was found to increase HLA class I molecule expression on the surface of MCF-7 cells, HLA class 1 and II molecule expression on the surface of MDA-453、 MKN-28、 MKN-45、 Hela and 3AO cells. The effect of sodium phenylacetate on HLA class I molecule expression in tumor cells is dose-and time-dependent.