{"id":26369,"date":"2018-08-20T14:55:55","date_gmt":"2018-08-20T18:55:55","guid":{"rendered":"https:\/\/www.tun.com\/blog\/?p=26369"},"modified":"2022-03-16T10:30:18","modified_gmt":"2022-03-16T14:30:18","slug":"breast-cells-attack-invading-cancer-cells","status":"publish","type":"post","link":"https:\/\/www.tun.com\/blog\/breast-cells-attack-invading-cancer-cells\/","title":{"rendered":"Breast Cells Can Actively Attack Invading Cancer Cells, Study Finds"},"content":{"rendered":"<p><span style=\"font-weight: 400;\">Researchers at Johns Hopkins University have recently discovered that the cell layer surrounding breast milk ducts, called the myoepithelium, <\/span><a href=\"https:\/\/hub.jhu.edu\/2018\/08\/02\/breast-cancer-metastasis-myoepithelium\/\"><span style=\"font-weight: 400;\">works as an active defense<\/span><\/a><span style=\"font-weight: 400;\"> against breast cancer metastasis. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">Scientists previously believed this cell layer only acted as a stationary barrier to prevent cancer invasion, but in a demonstration with mice, the Johns Hopkins team discovered that it actually reaches out and grabs stray cancer cells to prevent them from spreading throughout the body. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201cUnderstanding how cancer cells are contained could eventually help us develop ways to predict a person&#8217;s individualized risk of metastasis,&#8221; <\/span><a href=\"https:\/\/cellbio.jhmi.edu\/people\/faculty\/andrew-ewald-phd\"><span style=\"font-weight: 400;\">Andrew Ewald<\/span><\/a><span style=\"font-weight: 400;\">, a professor of cell biology at the university\u2019s School of Medicine and a member of the Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, said in a statement. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">The team includes <\/span><a href=\"https:\/\/cellbio.jhmi.edu\/people\/students\/orit-katarina-sirka\"><span style=\"font-weight: 400;\">Orit Katarina Sirka<\/span><\/a><span style=\"font-weight: 400;\">, a doctoral student student in Ewald&#8217;s laboratory, and <\/span><a href=\"https:\/\/profiles.ucsf.edu\/eliah.shamir\"><span style=\"font-weight: 400;\">Eliah Shamir<\/span><\/a><span style=\"font-weight: 400;\">, who is now a surgical pathology fellow at the University of California, San Francisco.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The research is published in the <\/span><a href=\"http:\/\/jcb.rupress.org\/content\/early\/2018\/07\/27\/jcb.201802144\"><span style=\"font-weight: 400;\">Journal of Cell Biology<\/span><\/a><span style=\"font-weight: 400;\">. <\/span><\/p>\n<h2><b>Myoepithelial layer <\/b><\/h2>\n<p><span style=\"font-weight: 400;\">Most breast tumors begin in the cells that line the interior of breast milk ducts, Ewald explained. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">These cells are surrounded by myoepithelial cells that work to contract and move milk through the ducts when a baby is breastfeeding. This layer is also used to clinically distinguish between contained breast cancers and invasive cancers. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">When cancer cells breach the myoepithelium, the result is called invasive carcinoma, which is associated with more aggressive treatment and higher rates of recurrence. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201cWe knew that the presence and integrity of the myoepithelial layer was key to the clinical management of breast cancer,\u201d said Ewald. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">Pathologists like <\/span><span style=\"font-weight: 400;\">Shamir<\/span><span style=\"font-weight: 400;\"> \u201c<\/span><span style=\"font-weight: 400;\">diagnose invasive breast cancer based on the presence of cancer cells past the myoepithelium,\u201d he explained.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201cDespite this clinical reality, it wasn\u2019t clear whether myoepithelial cells were markers of risk or whether they regulated invasive behavior. Very few experimental systems have modeled the myoepithelium in a realistic fashion,\u201d he continued.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Prior to this study, the understanding of myoepithelium was reminiscent of a castle wall, used as a barrier to block invasive cancer cells, Ewald said. <\/span><\/p>\n<h2><b>The study <\/b><\/h2>\n<p><span style=\"font-weight: 400;\">To determine the functions of myoepithelium, Ewald and his team engineered cells from the lining of mouse breast ducts to produce the protein Twist1, which has been linked to cancer metastasis in multiple tumor types. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">Surprisingly, they found that when the invasive Twist1 cells broke through the myoepithelial layer, the myoepithelial cells grabbed the escaping cells and pulled them back within the breast duct lining. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">&#8220;These findings establish the novel concept of the myoepithelium as a dynamic barrier to cell escape, rather than acting as a stone wall as it was speculated before,&#8221; Sirka said in a statement.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Through 114 observations, the researchers found that this happened 92 percent of the time. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201cWe were seeing in real-time that the myoepithelium was a dynamic barrier to epithelial invasion,\u201d Ewald said. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201cWe could literally see myoepithelial cells reach out and grab escaping cancer cells and pull them back into the tumor, thereby preventing their spread.\u201d<\/span><\/p>\n<figure style=\"width: 438px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" class=\"size-full\" src=\"https:\/\/api.hub.jhu.edu\/factory\/sites\/default\/files\/JCB_201802144_V2.gif\" width=\"438\" height=\"432\" \/><figcaption class=\"wp-caption-text\">Image: Ewald Laboratory<\/figcaption><\/figure>\n<h2><b>Continuing the test \u00a0<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">To further confirm this layer was active, the researchers altered two important characteristics of the myoepithelial cells: their ability to contract and their numerical ratio to invasive cells. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">They genetically engineered the mice cells to deplete their smooth muscle actin, a protein that enables cells to contract, making it more difficult for them to contract. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">Under that condition, the number of escaped invasive cells that broke through the myoepithelial layer increased three times compared to cells with a normal myoepithelium. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">The researchers also found that decreasing the proportion of myoepithelial cells to invasive cells increased the number of escaped cancer cells. Specifically, they found that adding two myoepithelial cells for one invasive cell decreases the escape rate four times more than it would with no defending barrier. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201cThis is important to know because it suggests that both the physical completeness of the myoepithelium and the gene expression within the myoepithelial cells are important in predicting the behavior of human breast tumors. Anywhere this layer thins or buckles is an opportunity for cancer cells to escape,&#8221; Shamir said in a statement. <\/span><\/p>\n<h2><b>What\u2019s next?<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">Moving forward, the team plans to study the cellular mechanisms and molecular requirements that prompt the myoepithelial layer to react so dynamically. \u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201cWe are working with pathologists to test whether either detection of small breaks in the myoepithelium or molecular analysis of the differentiation state of myoepithelial cells correlate with increased risk of metastatic recurrence,\u201d said Ewald.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201c<\/span><span style=\"font-weight: 400;\">We have also developed genetic approaches to kill myoepithelial cells in an inducible fashion; this will enable us to remove them at different stages of cancer progression and check whether metastasis is accelerated. We are also studying multiple breast cancer models to determine how they subvert this barrier, whether by killing, differentiating, or inducing the escape of myoepithelial cells.\u201d <\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Researchers at Johns Hopkins University have recently discovered that the cell layer surrounding breast milk ducts, called the myoepithelium, works as an active defense against breast cancer metastasis. Scientists previously believed this cell layer only acted as a stationary barrier to prevent cancer invasion, but in a demonstration with mice, the Johns Hopkins team discovered [&hellip;]<\/p>\n","protected":false},"author":58,"featured_media":26374,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_uag_custom_page_level_css":"","_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[350,241,230,229],"tags":[],"class_list":["post-26369","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-johns-hopkins-university","category-medical-breakthrough","category-news","category-lead-stories"],"aioseo_notices":[],"uagb_featured_image_src":{"full":["https:\/\/www.tun.com\/blog\/wp-content\/uploads\/2018\/08\/Johns-Hopkins-Cell-Defense-Cancer.jpg",830,533,false],"thumbnail":["https:\/\/www.tun.com\/blog\/wp-content\/uploads\/2018\/08\/Johns-Hopkins-Cell-Defense-Cancer-150x150.jpg",144,144,true],"medium":["https:\/\/www.tun.com\/blog\/wp-content\/uploads\/2018\/08\/Johns-Hopkins-Cell-Defense-Cancer-300x193.jpg",300,193,true],"medium_large":["https:\/\/www.tun.com\/blog\/wp-content\/uploads\/2018\/08\/Johns-Hopkins-Cell-Defense-Cancer.jpg",830,533,false],"large":["https:\/\/www.tun.com\/blog\/wp-content\/uploads\/2018\/08\/Johns-Hopkins-Cell-Defense-Cancer.jpg",830,533,false],"1536x1536":["https:\/\/www.tun.com\/blog\/wp-content\/uploads\/2018\/08\/Johns-Hopkins-Cell-Defense-Cancer.jpg",830,533,false],"2048x2048":["https:\/\/www.tun.com\/blog\/wp-content\/uploads\/2018\/08\/Johns-Hopkins-Cell-Defense-Cancer.jpg",830,533,false]},"uagb_author_info":{"display_name":"Natalie Colarossi","author_link":"https:\/\/www.tun.com\/blog\/author\/natalie-colarossi\/"},"uagb_comment_info":0,"uagb_excerpt":"Researchers at Johns Hopkins University have recently discovered that the cell layer surrounding breast milk ducts, called the myoepithelium, works as an active defense against breast cancer metastasis. Scientists previously believed this cell layer only acted as a stationary barrier to prevent cancer invasion, but in a demonstration with mice, the Johns Hopkins team discovered&hellip;","featured_media_src_url":"https:\/\/www.tun.com\/blog\/wp-content\/uploads\/2018\/08\/Johns-Hopkins-Cell-Defense-Cancer.jpg","_links":{"self":[{"href":"https:\/\/www.tun.com\/blog\/wp-json\/wp\/v2\/posts\/26369","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.tun.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.tun.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.tun.com\/blog\/wp-json\/wp\/v2\/users\/58"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tun.com\/blog\/wp-json\/wp\/v2\/comments?post=26369"}],"version-history":[{"count":0,"href":"https:\/\/www.tun.com\/blog\/wp-json\/wp\/v2\/posts\/26369\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.tun.com\/blog\/wp-json\/wp\/v2\/media\/26374"}],"wp:attachment":[{"href":"https:\/\/www.tun.com\/blog\/wp-json\/wp\/v2\/media?parent=26369"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.tun.com\/blog\/wp-json\/wp\/v2\/categories?post=26369"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.tun.com\/blog\/wp-json\/wp\/v2\/tags?post=26369"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}