THE RECAP TheRecapIssue#5 | Page 12

A BATTLE BETWEEN METASTASIZING TUMOR CELLS AND CHEMO MAYAR TAMER HIDE & SEEK WHAT HAPPENS WHEN OUR MAIN GO-TO TREATMENT FAILS TO TREAT PRIMARY TUMORS OF THE HEAD, NECK AND BREAST CANCERS? 12 For an extended period of time, health professionals in the field of oncology have depended on the use of chemotherapy to treat cancer patients despite the ongoing research and discovery in the field. But what happens when our main go-to treatment fails to treat primary tumors of the head, neck and breast cancers? cancer cells only, alongside other types of healthy cells that do multiply often such as hair and bone marrow cells. Now it may seem that chemotherapy does the job of curing cancer patients, but unfortunately not. Chemotherapy was found to fail in one condition. THE BIG PICTURE A LITTLE ABOUT THE ENEMY Cancer is characterized by uncontrolled abnormal cell growth leading to the formation of atypical bodies known as tumors. The concept of cell growth in a healthy cell is controlled by the cell cycle. A process that aims at controlling cell growth through cyclins-regulated stages of progression. In addition to regulating cell division, this process incorporates mechanisms that allow for errors to be either eliminated or for cell apoptosis occurring. However, in cancer patients this regulatory process faults, as a result of genetic mutations, leading to the uncontrolled cell growth. CHEMO AT WORK Chemotherapy is the general name given to treatment of cancer using drugs. But, to be more specific chemotherapy is the treatment using a combination of cytotoxic medicines that aim at interfering with some aspect of the cell division mechanism in order t o kill the cell or prevent its growth. Luckily enough however the majority of healthy cells in the body such as muscle cells, brain cells and bone cells do not divide very often, therefore allowing chemotherapy to mainly impact College of Medicine and Icahn School of Medicine at Mount Sinai began researching more to transform the way health professionals deal with treating metastatic disease. Together the group of investigators developed a device "using a nanotechnology tool; biosensors, coupled with advanced imaging technology to manipulate primary tumor microenvironments." In a study published in "Nature cell Biology" on 23rd January They implanted devices containing drugs that provoked 2017, scientists at the Mount Sinai School of Medicine hypoxia in tumors, allowing them to create controlled hypoxic revealed their discovery of a condition by which specific and non-hypoxic tumor environments. This setup allowed signals in primary tumors of certain cancers are capable of for the isolation of cancer cells to identify their change in reprogramming cancer cells to become dormant and evade behavior as they transition from primary tumors to other chemotherapy after metastasizing. organs such as the lungs. This was accompanied by tracking They elaborated that the cause of this ability is due to the DTCs with genetically encoded biosensors to determine hypoxia —which is a deficiency in the amount of oxygen which cells were exposed to low oxygen, which were dormant reaching the tissues— Hypoxia is a microenvironmental and how they reacted to therapy. distinctive feature of solid tumors that provokes stress responses, dormancy programs, and chemo and The investigators concluded that DTCs from hypoxic regions radioresistance. Similar effects apply in primary tumors. The were able to achieve metastases and more likely to enter study claims that primary tumor hypoxic microenvironments dormancy allowing them to be more efficient at evading lead to a subpopulation of dormant disseminated tumor cells chemotherapy. (DTCs) that also have the capability to evade therapy. Based on this, a group of investigators from Albert Einstein MEDICINE Furthermore the findings from this research allow for the development of a test that permits the prediction of which 13