Loss of primary cilia occurs early in breast cancer development

BACKGROUND:Primary cilia are microtubule-based organelles that protrude from the cell surface. Primary cilia play a critical role in development and disease through regulation of signaling pathways including the Hedgehog pathway. Recent mouse models have also linked ciliary dysfunction to cancer. However, little is known about the role of primary cilia in breast cancer development. Primary cilia expression was characterized in cancer cells as well as their surrounding stromal cells from 86 breast cancer patients by counting cilia and measuring cilia length. In addition, we examined cilia expression in normal epithelial and stromal cells from reduction mammoplasties as well as histologically normal adjacent tissue for comparison.RESULTS:We observed a statistically significant decrease in the percentage of ciliated cells on both premalignant lesions as well as in invasive cancers. This loss of cilia does not correlate with increased proliferative index (Ki67-positive cells). However, we did detect rare ciliated cancer cells present in patients with invasive breast cancer and found that these express a marker of basaloid cancers that is associated with poor prognosis (Cytokeratin 5). Interestingly, the percentage of ciliated stromal cells associated with both premalignant and invasive cancers decreased when compared to stromal cells associated with normal tissue. To understand how cilia may be lost during cancer development we analyzed the expression of genes required for ciliogenesis and/or ciliary function and compared their expression in normal versus breast cancer samples. We found that expression of ciliary genes were frequently downregulated in human breast cancers.CONCLUSIONS:These data suggest that primary cilia are lost early in breast cancer development on both the cancer cells and their surrounding stromal cells.This item is part of the UA Faculty Publications collection. For more information this item or other items in the UA Campus Repository, contact the University of Arizona Libraries at [email protected]

Posttranscriptional Suppression of Proto-Oncogene c-fms Expression by Vigilin in Breast Cancer ▿ §

cis-acting elements found in 3′-untranslated regions (UTRs) are regulatory signals determining mRNA stability and translational efficiency. By binding a novel non-AU-rich 69-nucleotide (nt) c-fms 3′ UTR sequence, we previously identified HuR as a promoter of c-fms proto-oncogene mRNA. We now identify the 69-nt c-fms mRNA 3′ UTR sequence as a cellular vigilin target through which vigilin inhibits the expression of c-fms mRNA and protein. Altering association of either vigilin or HuR with c-fms mRNA in vivo reciprocally affected mRNA association with the other protein. Mechanistic studies show that vigilin decreased c-fms mRNA stability. Furthermore, vigilin inhibited c-fms translation. Vigilin suppresses while HuR encourages cellular motility and invasion of breast cancer cells. In summary, we identified a competition for binding the 69-nt sequence, through which vigilin and HuR exert opposing effects on c-fms expression, suggesting a role for vigilin in suppression of breast cancer progression

Correlation of ROS1 Immunohistochemistry With ROS1 Fusion Status Determined by Fluorescence In Situ Hybridization

International audienceThe ability to determine ROS1 status has become mandatory for patients with lung adenocarcinoma, as many global authorities have approved crizotinib for patients with ROS1-positive lung adenocarcinoma