The Hh pathway is activated in breast tumors.

<p>Breast cancer tissues (n = 75) and normal breast tissues (n = 9) were immunohistochemically stained for (<b>A</b>) IHH and (<b>B</b>) GLI1 expression. The intensity of cytoplasmic staining was quantitated with computer-assisted image analysis in a Dako ACIS III Image Analysis System (Glostrup, Denmark). Staining intensities were recorded and represented as a scatter plot. The staining intensities indicating expression levels of IHH and GLI1 were significantly greater (p<0.0001) in the tissues derived from invasive cancer (representing Infiltrating Ductal Carcinoma Grades II–IV) and from metastatic breast cancer (DM) relative to normal tissues and tissues derived from Ductal Carcinoma In Situ (DCIS). Panels <b>a</b> and <b>b</b> represent normal breast tissue and invasive breast cancer stained for IHH. Panels <b>c</b> and <b>d</b> represent normal breast tissue and invasive breast cancer stained for GLI1.