Radiation therapy or radiotherapy, often abbreviated RT, RTx, or XRT, is a therapy using ionizing radiation, generally provided as part of cancer treatment to control or kill malignant cells and normally delivered by a linear accelerator. Radiation therapy may be curative in a number of types of cancer if they are localized to one area of the body. It may also be used as part of adjuvant therapy, to prevent tumor recurrence after surgery to remove a primary malignant tumor. Radiation therapy is synergistic with chemotherapy, and has been used before, during, and after chemotherapy in susceptible cancers. The subspecialty of oncology concerned with radiotherapy is called radiation oncology. A physician who practices in this subspecialty is a radiation oncologist.
Angiogenesis is the physiological process through which new blood vessels form from pre-existing vessels, formed in the earlier stage of vasculogenesis. Angiogenesis continues the growth of the vasculature by processes of sprouting and splitting. Vasculogenesis is the embryonic formation of endothelial cells from mesoderm cell precursors, and from neovascularization, although discussions are not always precise. The first vessels in the developing embryo form through vasculogenesis, after which angiogenesis is responsible for most, if not all, blood vessel growth during development and in disease.
Tumor hypoxia is the situation where tumor cells have been deprived of oxygen. As a tumor grows, it rapidly outgrows its blood supply, leaving portions of the tumor with regions where the oxygen concentration is significantly lower than in healthy tissues. Hypoxic microenvironements in solid tumors are a result of available oxygen being consumed within 70 to 150 μm of tumour vasculature by rapidly proliferating tumor cells thus limiting the amount of oxygen available to diffuse further into the tumor tissue. In order to support continuous growth and proliferation in challenging hypoxic environments, cancer cells are found to alter their metabolism. Furthermore, hypoxia is known to change cell behavior and is associated with extracellular matrix remodeling and increased migratory and metastatic behavior.
An antimetabolite is a chemical that inhibits the use of a metabolite, which is another chemical that is part of normal metabolism. Such substances are often similar in structure to the metabolite that they interfere with, such as the antifolates that interfere with the use of folic acid; thus, competitive inhibition can occur, and the presence of antimetabolites can have toxic effects on cells, such as halting cell growth and cell division, so these compounds are used as chemotherapy for cancer.
The enhanced permeability and retention (EPR) effect is a controversial concept by which molecules of certain sizes tend to accumulate in tumor tissue much more than they do in normal tissues. The general explanation that is given for this phenomenon is that, in order for tumor cells to grow quickly, they must stimulate the production of blood vessels. VEGF and other growth factors are involved in cancer angiogenesis. Tumor cell aggregates as small as 150–200 μm, start to become dependent on blood supply carried out by neovasculature for their nutritional and oxygen supply. These newly formed tumor vessels are usually abnormal in form and architecture. They are poorly aligned defective endothelial cells with wide fenestrations, lacking a smooth muscle layer, or innervation with a wider lumen, and impaired functional receptors for angiotensin II. Furthermore, tumor tissues usually lack effective lymphatic drainage. All of these factors lead to abnormal molecular and fluid transport dynamics, especially for macromolecular drugs. This phenomenon is referred to as the "enhanced permeability and retention (EPR) effect" of macromolecules and lipids in solid tumors. The EPR effect is further enhanced by many pathophysiological factors involved in enhancement of the extravasation of macromolecules in solid tumor tissues. For instance, bradykinin, nitric oxide / peroxynitrite, prostaglandins, vascular permeability factor, tumor necrosis factor and others. One factor that leads to the increased retention is the lack of lymphatics around the tumor region which would filter out such particles under normal conditions.
The Warburg hypothesis, sometimes known as the Warburg theory of cancer, postulates that the driver of tumorigenesis is an insufficient cellular respiration caused by insult to mitochondria. The term Warburg effect in oncology describes the observation that cancer cells, and many cells grown in vitro, exhibit glucose fermentation even when enough oxygen is present to properly respire. In other words, instead of fully respiring in the presence of adequate oxygen, cancer cells ferment. The Warburg hypothesis was that the Warburg effect was the root cause of cancer. The current popular opinion is that cancer cells ferment glucose while keeping up the same level of respiration that was present before the process of carcinogenesis, and thus the Warburg effect would be defined as the observation that cancer cells exhibit glycolysis with lactate production and mitochondrial respiration even in the presence of oxygen.
VIB is a research institute located in Flanders, Belgium. It was founded by the Flemish government in 1995, and became a full-fledged institute on 1 January 1996. The main objective of VIB is to strengthen the excellence of Flemish life sciences research and to turn the results into new economic growth. VIB spends almost 80% of its budget on research activities, while almost 12% is spent on technology transfer activities and stimulating the creation of new businesses, in addition VIB spends approximately 2% on socio-economic activities. VIB is member of EU-LIFE, an alliance of leading life sciences research centres in Europe.
Frans Van Roy is a Belgian molecular biologist and professor at the University of Ghent. He is head of the VIB Department for Molecular Biomedical Research, UGent. His research interest is on the molecular mechanisms underlying the pathology and the cure of cancer and inflammation-related disorders.
The term nanocell refers to a drug delivery platform consisting of a polymer-bound chemotherapeutic drug combined with a lipid-bound anti-angiogenesis drug. Nanocells are currently being developed in the lab of Shiladitya Sengupta of MIT.
A liver metastasis is a malignant tumor in the liver that has spread from another organ affected by cancer. The liver is a common site for metastatic disease because of its rich, dual blood supply. Metastatic tumors in the liver are 20 times more common than primary tumors. In 50% of all cases the primary tumor is of the gastrointestinal tract; other common sites include the breast, ovaries, bronchus and kidney. Patients with Colorectal cancer will develop liver metastases during the disease
A radiosensitizer is an agent that makes tumor cells more sensitive to radiation therapy. It is sometimes also known as a radiation sensitizer or radio-enhancer.
The University of Wisconsin Carbone Cancer Center (UWCCC) is a comprehensive cancer center in Wisconsin, as designated by the National Cancer Institute (NCI), the lead federal agency for cancer research. It is an integral part of both the University of Wisconsin (UW) and the University of Wisconsin Hospital and Clinics. It is located in Madison, Wisconsin.
Osteoradionecrosis (ORN) is a serious complication of radiation therapy in cancer treatment where radiated bone becomes necrotic and exposed. ORN occurs most commonly in the mouth during the treatment of head and neck cancer, and can arise over 5 years after radiation. Common signs and symptoms include pain, difficulty chewing, trismus, mouth-to-skin fistulas and non-healing ulcers.
Hepatic artery embolization, also known as trans-arterial embolization (TAE), is one of the several therapeutic methods to treat primary liver tumors or metastases to the liver. The embolization therapy can reduce the size of the tumor, and decrease the tumor's impact such its hormone production, effectively decreasing symptoms. The treatment was initially developed in the early 1970s. The several types of hepatic artery treatments are based on the observation that tumor cells get nearly all their nutrients from the hepatic artery, while the normal cells of the liver get about 70-80 percent of their nutrients and 50% their oxygen supply from the portal vein, and thus can survive with the hepatic artery effectively blocked. In practice, hepatic artery embolization occludes the blood flow to the tumors, achieving significant tumor shrinkage in over 80% of people. Shrinkage rates vary.
William G. Kaelin Jr. is an American Nobel laureate physician-scientist. He is a professor of medicine at Harvard University and the Dana–Farber Cancer Institute. His laboratory studies tumor suppressor proteins. In 2016, Kaelin received the Albert Lasker Award for Basic Medical Research and the AACR Princess Takamatsu Award. He also won the Nobel Prize in Physiology or Medicine in 2019 along with Peter J. Ratcliffe and Gregg L. Semenza.
Núria López Bigas is a Spanish biologist and research professor with expertise in medical genetics, computational biology, and bioinformatics. She is an ICREA professor at Pompeu Fabra University and she also leads the Biomedical Genomics Research Group at the Institute for Research in Biomedicine in Barcelona, Spain. Her research is focused on developing computational approaches to investigate cancer genomes.
Epitopoietic Research Corporation (ERC) is a Belgian Pharmaceutical company developing ERC1671, which specialise in treatment for Glioblastoma multiforme which is the most aggressive form of brain cancer. In 2019, ERC became the first pharmaceutical company to provide treatment under the US Federal Right-to-try law.
Michele 'Miki' De Palma is an Italian biologist and a professor at EPFL. He is known for his work on the role of macrophages in cancer progression and the discovery of Tie2-expressing angiogenic monocytes.
Stein Aerts is a Belgian bio-engineer and computational biologist. He leads the Laboratory of Computational Biology at VIB and KU Leuven, and has received several accolades for his research into the workings of the genomic regulatory code.
Reuven Agami is a Dutch cancer researcher. He is a professor of Oncogenomics at Erasmus University Rotterdam and head of the section of Oncogenomics at the Netherlands Cancer Institute-Antoni van Leeuwenhoekziekenhuis.
