Cell Growth & Differentiation, Vol 1, Issue 5 225-231, Copyright © 1990 by American Association of Cancer Research
Association of hst gene expression with metastatic phenotype in mouse mammary tumors
A Murakami, H Tanaka and A Matsuzawa
Department of Viral Oncology, Institute for Virus Research, Kyoto University, Japan.
From the pregnancy-dependent mouse mammary tumor TPDMT-4, four autonomous
sublines were established after its independent progression under different
conditions. Despite their similar growth rates in inguinal fat pads, three
sublines formed lung metastases, and one did not when they were injected
i.v. into mice as a single cell suspension. The TPDMT-4 tumor and the
nonmetastatic subline expressed mRNA for the orf gene of mouse mammary
tumor virus, whereas all metastatic sublines did not. This suggested that
the loss of its expression may have been a prerequisite for the progression
toward metastatic ability. To identify the gene(s) participating in the
generation and the progression of TPDMT-4, the expression of 23 different
oncogenes was analyzed. The expression of int-2 was detected in TPDMT-4 and
in all sublines, indicating that TPDMT-4 was generated by activation of
this gene, whereas hst expression occurred only in the metastatic sublines.
These results demonstrated that the hst gene may contribute to tumor
progression from a nonmetastatic to a metastatic phenotype in the mouse
mammary tumor system.