Comparison of HLA-G and MMP transcription in human tumor cell lines.

HLA-G antigens and matrix metalloproteinases (MMPs) expressed in various tumors are involved in tumor growth and metastasis. In this study, we investigated if correlation between HLA-G and MMP expression exists in different cell lines. We examined MMP transcription in two choriocarcinoma cell lines: JEG-3 (HLA-G positive) and JAR (HLA-G negative). We discovered that both cell lines express a similar panel of MMPs; except for MMP12. Transcript MMP12 was exclusively detected in HLA-G expressing JEG-3 cells but not in HLA-G deficient JAR cells. We observed HLA-G expression but no MMP12 transcription following 5-aza-2'-deoxycytidine (AZA) treatment of JAR cells. We then investigated HLA-G and MMP transcription in several human leukaemia cell lines. Leukaemia cells (lacking HLA-G expression) were converted to their HLA-G positive counterparts by AZA-treatment or by HLA-G transfection. It was found no correlation between HLA-G and MMP transcription in any examined leukaemia cell lines. The up-regulation of some MMPs and tissue inhibitors of matrix metalloproteinases (TIMPs) was observed following AZA-treatment.