LAUSR

LAM pathogenesis to determine druggable targets. The data on the LAM cell, its gene expression pattern, and its effect on its microenvironment were generated with the input of only three LAM lungs owing to the difficulty of obtaining fresh tissue samples. However, many of the pathways and processes proposed here fit with data already available about LAM pathogenesis. It is interesting to note that LAM cells could not be detected in the lung from a patient who had been taking sirolimus, the only approved drug for LAM that was tested in a double-blind clinical trial (14), suggesting that the LAM cell is sensitive to sirolimus and is indeed involved in disease pathogenesis. It would be interesting to see the expression pattern of the metastatic, circulating LAM cells and if they differ from the LAM cell. And although the theorized uterine origin of the LAM cell is promising and deserves further investigation, it does not explain the rare occurrence of LAM in males (15). LAM cells in the lung may arise from another site, which would, of necessity, be the case in males. Nevertheless, this study has given the LAM scientific community opportunities for future studies and represents a major advance in our understanding of this disease. n