Fig. 3.

CREB3L1 is required for metastasis and is upregulated in the metastases of breast cancer patients. a A quantification of circulating tumor cells (CTCs) per ml of blood from NOD/SCID mice 7 weeks after being transplanted with MDA.MB.231-Luc-LM2 cells transduced with shRNAs targeting LacZ or CREB3L1, n = 5. b Lung metastases of the animals in a were quantified (top) by radiance of the whole lung in each animal, n = 5. Total radiance was also imaged (bottom). c Lung metastases of the animals in a was gauged by immunohistochemistry staining for GFP-positive cancer cells in lung sections. GFP area per field was quantified (top) and imaged (bottom), n = 10,10,9 for Ctrl, sh1, and sh2, respectively (scale bar: 40 µm). d Expression of CREB3L1 in 529 primary breast cancer tissues and 45 breast cancer metastases (GSE20565, GSE20685, GSE7904, and GSE3744) shown as a box-and-whiskers plot. e Immunohistochemical staining for CREB3L1 in a tissue microarray containing primary breast cancer tissues (left, n = 50) and breast cancer metastases in lymph nodes (middle, n = 50). Nuclear CREB3L1 levels were quantified (right). Scale bar: 40 µm. Data are represented as mean ± SEM or the mean alone. * indicates p < 0.05; ** indicates p < 0.01 (Student’s t-test)