Researchers use DNA origami to generate tiny mechanical devices that deliver a drug that cuts off the blood supply to tumors in mice.
Improved methods to grow patients’ tumor cells in a dish offer opportunities to find durable therapies.
November 17, 2014|
FLICKR, ANNE WESTON, LRI, CROK. WELLCOME IMAGESCancers can become resistant to drugs that once seemed like they could cure a person of the disease. In the unstopping march toward personalized medicine, researchers managed to culture drug-resistant lung tumor cells to screen them for sensitivity to various therapies, finding new and sometimes surprising drug candidates.
“It’s a substantial step,” Jeffrey Engelman of Massachusetts General Hospital Cancer Center told Time. “Because before we just had the genetic information but we wouldn’t have the cells alive so that we could test what types of therapies might work.”
Engelman and his colleagues published their study in Science last week (November 13). They succeeded in growing cells taken from 20 patients’ tumors. Nature News pointed out that, in many cases, the drug screens turned up unexpected candidates. In half of the tumors, for example, a drug that inhibits a protein called SRC managed to shrink tumor growth in vitro. “There were no genetic results that would have pointed to that combination,” Engelman told Nature News.
Engelman’s method has yet to face a clinical challenge; patients’ therapies were not altered based on the screen. “This is really setting up the criteria for what we have to look at next,” Richard Schlegel, director of the Center for Cell Reprogramming at Georgetown University School of Medicine, told the Boston Globe. “Someone has to figure out if we grow up these cells, how many times is this going to be an adequate predictor of patient response?”
February 28, 2015
Cancer Drug Resistance, Personalized Medicine and Father of Oncology. Cancer is an individual disease. All modern cancer therapies are limited by the development of drug resistance. Chemotherapy is one of the principal modes of treatment for cancer, but the effectiveness of chemotherapy is limited by drug resistance. Chemotherapy resistance occurs when cancers that have been responding to a therapy suddenly begin to grow. Malignant tumors usually consist of mixed populations of malignant cells, some of which are drug-sensitive while others are drug-resistant. Chemotherapy kills drug-sensitive cells, but leaves behind a higher proportion of drug-resistant cells. Before personalized medicine, most patients with a specific type and stage of cancer received the same treatment. In cancer, personalized medicine uses specific information about a person’s tumor to help diagnose, plan treatment, find out how well treatment is working, or make a prognosis. Although personalized medicine is a new and exciting approach to cancer treatment, doctors still don't know everything about the genetic changes that occur in a cancerous cell. Cancer is a heterogeneous disease. Different regions of a tumor often have different molecular features at the genetic and protein levels, and this intratumoral molecular heterogeneity is thought to cause drug resistance and treatment failure in cancer. There is considerable genetic diversity between different tumors of the same type, and even within a tumor. There are many thousands of cancer sub-types. In fact each individual cancer is genetically unique - which supports the approach known as personalized medicine. The Father of Oncology says that primary tumors always develop at body sites of excessive iron deposits. Such deposits can be inherited or acquired. Cancer is a disease of iron-overloaded cells. Cancer occurs when cellular iron overload chaotically affects cellular molecules and organelles (DNA, chromosomes, mitochondria, lysosomes, peroxisomes, etc). Unfortunately, iron/cancer information-1905-2015 is largely ignored. A criminal conspiracy takes place when two or more people plan to commit a crime and then take some action toward carrying out that plan. Society decides what is and is not a crime through its system of laws. Genetic instability is a characteristic of all cancers because cellular iron overload chaotically affects DNA and chromosomes in cancerous cells. Personalized surgery (ceramic blades), personalized direct intratumoral injections of iron-deficiency agents (ceramic needles) and personalized clinical iron-deficiency methods (special diets, blood donations, etc.) can successfully neutralize tumors, metastases and micrometastases in hospitalized patients. http://www.medicalnewstoday.com/opinions/183391 ; https://www.the-scientist.com/?articles.view/articleNo/41449/title/Culturing-Drug-Resistant-Tumors/#articleCommentForm ; Vadim Shapoval