Reduced tumorigenicity of murine leukemia cells expressing protein-tyrosine phosphatase, PTPepsilon C.
Recently, we reported that a cytosolic isoform of protein-tyrosine phosphatase epsilon (PTP epsilon C), when overexpressed, inhibits terminal differentiation and apoptosis of murine M1 myeloblastic leukemia cells induced by interleukin-6. To determine whether these observed effects in vitro correspond to a tumorigenicity of PTP epsilon C-expresser (M1- epsilon C) cells in vivo, parent M1 and M1- epsilon C cells were intravenously inoculated into scid or nude mice, and survival of mice receiving these cell lines was monitored. Unexpectedly, both scid and nude mice inoculated with M1- epsilon C cells showed significantly prolonged survival time than those receiving parent M1 cells. While parent M1 cells inoculated by intravenous injection formed metastatic tumors in the spleen, expression of PTP epsilon C suppressed tumor development in the spleen. The results suggest a suppressive role of PTP epsilon C in tumorigenesis.
Tanuma
Nobuhiro
N
Division of Biochemical Oncology and Immunology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan.
Shima
Hiroshi
H
Shimada
Shigeki
S
Kikuchi
Kunimi
K
D000818:Animals; D007942:Leukemia, Experimental / Q000201:enzymology* / Q000473:pathology; D015470:Leukemia, Myeloid, Acute / Q000201:enzymology* / Q000473:pathology; D051379:Mice; D008819:Mice, Nude; D016513:Mice, SCID; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D017027:Protein Tyrosine Phosphatases