transforming-growth-factor-beta and Retroperitoneal-Neoplasms

We investigated whether transforming growth factor beta (TGF-beta) is involved in the growth of malignant mesothelioma (MM) cells in culture. TGF-beta production was examined in two mesothelioma cell lines (MeET-4 and -6) that were established from rat spontaneous MM in our laboratory. TGF-beta bioactivity in conditioned medium of these cell lines was analyzed using a CCL64 mink lung epithelial cell growth inhibition assay and found to be 30-70 times higher than that of normal rat mesothelial cells (MCs). The MM cell lines also showed considerably higher levels of TGF-beta mRNA expression when compared with MCs. The bioactivity and mRNA expression level were greater in MeET-4 than MeET-6. When MeET-4 was treated with antisense TGF-beta1 oligonucleotide (ODN), a significant decrease in both anchorage-dependent and -independent growth was observed. Treatment with exogenous TGF-beta resulted in no effects on the growth pattern of the MM cell lines, while proliferation of the MCs was slightly induced. It is considered that TGF-beta appears to be produced by rat spontaneous MM cells through an autocrine mechanism and could modulate the malignant growth of the tumor cells.

Topics: Animals; Cell Count; Cell Division; Culture Media, Conditioned; DNA Primers; Dose-Response Relationship, Drug; Epithelium; Mesothelioma; Molecular Sequence Data; Oligonucleotides, Antisense; Peritoneum; Polymerase Chain Reaction; Rats; Rats, Inbred F344; Retroperitoneal Neoplasms; RNA, Messenger; RNA, Neoplasm; Transforming Growth Factor beta; Tumor Cells, Cultured