SPP1 and invasive carcinoma: Consistent with these RNA analyses, fluorescent IHC on two human breast cancer tissue microarrays (BC081120f and BR1504b) for OPN revealed that 68% (13 out of 19) of adjacent normal tissue cores were OPN positive whereas 88% (200 out of 226) invasive carcinoma cores were OPN positive (Fig. 7b, c).