Happy Breast Cancer Awareness Month. A cancer is described as metastatic when cells break off from a primary tumor and spread to other parts of the body. For example, if breast cancer cells travel to the lungs and form a tumor there, that is a metastasis, or a metastatic breast cancer tumor, not lung cancer. Even one cancerous cell can break off a tumor, travel through the bloodstream and lodge itself in new tissue. Metastatic cells can start growing into tumors of their own right away, but often lie dormant for days, weeks, or even decades, only to flare up long after the primary tumor has been removed. Metastases cause the vast majority of cancer deaths, particularly in the case of breast cancer, where the original tumor is rarely deadly on its own. But the process by which cancer cells escape a primary tumor, invade other parts of the body, and seed new cancerous growths is poorly understood. In breast cancer in particular, we suspect that metastases are influenced by the intrinsically stem-cell-like genetic programs needed for breast tissue to grow during puberty and pregnancy. Only a small fraction of cancer research funding goes towards understanding metastases, partly because these tiny rogue cells are hard to find and study. As a result, deadly metastatic cancers are still extremely difficult to treat. Most cancer drugs are developed to shrink primary tumors, and they often don’t perform as well on metastatic tumors. My lab at UCSF is trying to uncover the biological mechanism underlying metastasis so we can finally understand how tumors shed cells, how the cells travel, how they survive, how they grow into new tumors, and how to stop them. In particular, we’re interested in how the local biological environment influences metastases that land in different parts of the body. Here’s a UCSF article a recent finding from my work: Metastatic Breast Cancer Cells Turn On Stem Cell Genes Here’s my lab at UCSF I’ll be back at 1 pm Et (10 am PT, 5 pm UTC) to answer your questions, ask me anything! EDIT: I am signed on. I am getting ready to answer questions. EDIT: Thanks for the questions. I am now signing off and getting back to research.