SLIT2 and breast cancer: However, expression of the other seven RNAs in the PAFs behaved the opposite way to what was expected, being upregulated (Timp1, Slit2, Igf1, Vcan, Ctsc) or downregulated (Tgfbi, Vtn) in PAFs during pregnancy, but in the human breast cancers this expression pattern was associated with improved rather than poor DMFS (see Additional file 11: Figure S8C).