[Enhancement of tumorigenesis and invasive capacity of regressor tumor cell by growth factors].
Tumorigenesis and invasive capacity of tumor cells are affected by the interactions between the tumor cells and the host cells; in particular, they are regulated by growth factors released from host cells. We have studied the effect of growth factors and cytokine on tumorigenesis and invasive capacity of tumor cells by examining a regressor tumor cell line (ER-1) derived from SHR rat mammary adenocarcinoma. The regressor tumor cells grew progressively in immunosuppressed rats, but spontaneously regressed in normal rats. We studied in vitro effect of growth factors on invasive capacity of ER-1 tumor cells into mesothelial cells obtained from SHR rats. As the results, pretreatment with EGF or TGF-beta significantly enhanced invasive capacity of ER-1 cells, whereas TNF-alpha did not show any effect. We pretreated ER-1 cells with EGF or TGF-beta for 24 hours in vitro, and then intraperitoneally transplanted them into SHR rats. The treated regressor tumor cells grew and killed the host. These results suggest that tumorigenesis and invasive capacity of regressor tumor cells are mediated by growth factors which promote growth and invasive abilities of tumor cells.
Li
X B
XB
Laboratory of Pathology, Hokkaido University School of Medicine, Sapporo, Japan.
D000230:Adenocarcinoma / Q000473:pathology*; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D004815:Epidermal Growth Factor / Q000494:pharmacology; D005260:Female; D006133:Growth Substances / Q000494:pharmacology*; D015674:Mammary Neoplasms, Animal / Q000473:pathology*; D009361:Neoplasm Invasiveness; D051381:Rats; D011918:Rats, Inbred SHR; D016212:Transforming Growth Factor beta / Q000494:pharmacology; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D006133:Growth Substances; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha; D004815:Epidermal Growth Factor