Saturday, 16 January 2016

Magic bullet for cancer


Chemotherapy for cancer is plagued by side-effects: generally, to kill the cancer, extremely powerful poisons are used. May or may not kill the cancer, but almost kills the patient.

But, what if chemotherapy drugs could be delivered only to the cancer, without poisoning the rest of the patient’s body? This is the “magic bullet”, first suggested by Dr. Paul Ehrlich (1854–1915).

Paclitaxel is a chemotherapy drug, commonly used to treat breast, lung & pancreatic cancers. Its purpose is to slow growth, by preventing cancer cells from replicating. Unfortunately, the patient’s body mounts an immune response against Paclitaxel, requiring an increased dose, causing hair loss, muscle & joint pain, diarrhea & suppression of the immune system.

At the University of North Carolina, Chapel Hill, scientists have been experimenting with exosomes (part of the immune system) as the magic bullet to deliver Paclitaxel. Being part of the immune system, exosomes are not themselves attacked by it.

In-vitro trials show that the exosomes swarm around a tumour, delivering Paclitaxel directly to the cancer. In this way, effective treatment is achieved using one fiftieth of the drug dose which would otherwise be required.


Drug-resistant lung cancer cells are in red. Paclitaxel-loaded exosomes (green) swarm the cancer cells, overcoming their drug resistance.
Credit: University of North Carolina Eshelman School of Pharmacy/Science Daily

http://www.sciencedaily.com/releases/2016/01/160114113632.htm

http://www.gizmag.com/drug-delivery-method-cancer-dose/41349/
/ Researchers kill drug-resistant lung cancer with 50 times less chemo cancer drugs packaged in immune bubbles home in directly to tumors without getting sidetracked and destroyed; less chemo with better results University of North Carolina at Chapel Hill cancer drug paclitaxel more effective for the first time researchers packaged containers derived from a patient's own immune system protect protection protecting drug destroyed body's own defenses delivering entire payload to the tumor cancer drug paclitaxel just became more effective researchers University of North Carolina Chapel Hill packaged containers patient's own immune system protecting drug body's own defenses entire payload tumor use 50 times less of the drug same results, Elena Batrakova Ph.D. associate professor UNC Eshelman School of Pharmacy treat patients smaller more accurate doses of powerful chemotherapy drugs more effective treatment fewer milder side effects Batrakova colleagues UNC Eshelman School of Pharmacy's Center for Nanotechnology in Drug Delivery exosomes tiny spheres harvested from white blood cells protect body against infection exosomes same material as cell membranes patient's body doesn't recognize them as foreign plastics-based nanoparticles drug-delivery systems exosomes engineered by nature perfect delivery vehicles technique potential therapy Parkinson's disease using exosomes from white blood cells wrap medicine invisibility cloak hides from immune system exosomes swarm cancer cells completely bypassing drug resistance delivering their payload Paclitaxel potent drug first second-line treatment breast lung pancreatic cancers serious unpleasant side effects hair loss muscle joint pain diarrhea patients greater risk of serious infection experiment Batrakova's team extracted exosomes mouse white blood cells loaded them with paclitaxel tested treatment exoPXT multiple-drug-resistant cancer cells petri dishes team needed 50 times less exoPXT achieve the same cancer-killing effect formulations drug currently Taxol researchers tested therapy mouse models drug-resistant lung cancer loaded exosomes dye track their progress lungs exosomes thorough seeking out marking cancer cells surprisingly effective diagnostic tool powerful therapeutic accurately mapping extent of tumors lungs biggest challenges treating lung-cancer patients Batrakova results powerful exosomes therapeutic diagnostic /