Previous studies performed in our laboratory showed that in vivo or in vitro treatment of murine lymphomas with triazene compounds (TZC) induces the appearance of novel tumor-associated antigens (i.e. 'chemical xenogenization', CX), or of membrane structures susceptible to natural immunity (NI), i.e. NI-related CX (CX/NI). The present investigation was performed to explore whether CX/NI could be induced in cultured human melanoma cells by treatment with monomethyl-triazene-benzoic acid potassium salt (MTBA), an in vitro active TZC. The results show that 2 over 3 MTBA-treated lines became more susceptible than the original melanoma to natural cytotoxic effector cells (i.e. NK or LAK cells). TZC-treated melanomas did not show substantial changes with respect to untreated tumors in the expression of HLA class I or class II antigens and of two epitopes of a high-molecular weight melanoma-associated antigen. In addition parental and MTBA-treated lines were scarcely susceptible to killing by 66 h continuous exposure to MTBA, whereas all lines were sensitive to Cisplatin and with the exception of one MTBA-treated line to Ara-C. Therefore no relationship was found between chemosensitivity to MTBA and susceptibility to a presumable induction of CX/NI by the same agent. The present study suggests the hypothesis that in vivo CX/NI could play a potential role in TZC-based chemoimmunotherapy of melanoma patients.
|Number of pages||13|
|Journal||Clinical Chemistry and Enzymology Communications|
|Publication status||Published - 1993|
- Natural immunity
ASJC Scopus subject areas
- Clinical Biochemistry