Walter H. Günzburg

Spleen specific expression of an MMTV related transcript associated with the Mtv-6 locus in BALB/c mice

We have detected an MMTV related transcript which is expressed in a spleen specific manner in BALB/cHeA mice. Using a recombinant inbred series between BALB/cHeA and STS/A mice (C X S RI series) we have identified RNA associated with the Mtv-3 locus of the STS/A strain. This transcript initiates at the same site in the MMTV LTR as already reported for Mtv-2 and Mtv-8. The novel spleen specific MMTV transcript in the BALB/cHeA strain has a different structure as compared to the transcripts associated with the Mtv-2, Mtv-3, or Mtv-8 loci. We have tentatively identified the Mtv-6 locus as the source of these unique transcripts.

Tumorigenic Conversion of in vivo Differentiation Competent Mammary Cells by Introduction and Expression of ras or mil(raf) but not myc

Mammary cancer affects around 9% of women and is the most frequent cause of death in women aged between 40 to 54 years old (Miller and Bulbrook, 1986). Whilst the mechanisms involved in mammary tumorigene fs are not understood, there is evidence for the existence of a human mammary tumour virus that is related to the Mouse Mammary Tumour Virus (MMTV) (Schlom et al., 1971; Crepin et al., 1984; Keydar et al., 1984; Ono et al., 1986; Ono et al., 1987; Franklin et al., 1988). Additionally, a number of oncogenes have been implicated in the tumorigenic process. Elevated expression and/or amplification of the oncogenes ras, myc and neu have been correlated with human mammary tumorigenesis (Horan-Hand et al., 1984; DeBortoli et al., 1985; Ohuchi et al., 1986; Kraus et al., 1984; King et al., 1985; Slamon et al., 1987; Kozbor and Croces, 1984; Escot et al., 1986; Varley et al., 1987).