Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom, e.g. from the puff adder or brown recluse spider.
Cytarabine, also known as cytosine arabinoside (ara-C), is a chemotherapy medication used to treat acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), chronic myelogenous leukemia (CML), and non-Hodgkin's lymphoma. It is given by injection into a vein, under the skin, or into the cerebrospinal fluid. There is a liposomal formulation for which there is tentative evidence of better outcomes in lymphoma involving the meninges.
Tirapazamine (SR-4233) is an experimental anticancer drug that is activated to a toxic radical only at very low levels of oxygen (hypoxia). Such levels are common in human solid tumors, a phenomenon known as tumor hypoxia. Thus, tirapazamine is activated to its toxic form preferentially in the hypoxic areas of solid tumors. Cells in these regions are resistant to killing by radiotherapy and most anticancer drugs. Thus the combination of tirapazamine with conventional anticancer treatments is particularly effective. As of 2006, tirapazamine is undergoing phase III testing in patients with head and neck cancer and gynecological cancer, and similar trials are being undertaken for other solid tumor types.
Streptozotocin or streptozocin (STZ) is a naturally occurring alkylating antineoplastic agent that is particularly toxic to the insulin-producing beta cells of the pancreas in mammals. It is used in medicine for treating certain cancers of the islets of Langerhans and used in medical research to produce an animal model for hyperglycemia in a large dose, as well as type 2 diabetes or type 1 diabetes with multiple low doses.
The Walker Cancer Research Institute (WCRI) is an American cancer research organization consisting of two laboratories located in the states of Florida and Michigan and principal organizational offices in Maryland. WCRI and the affiliated project National Cancer Research Center (NCRC) were incorporated as nonprofit 501(c)(3) charitable organizations in 1981.
Lapatinib (INN), used in the form of lapatinib ditosylate (USAN) is an orally active drug for breast cancer and other solid tumours. It is a dual tyrosine kinase inhibitor which interrupts the HER2/neu and epidermal growth factor receptor (EGFR) pathways. It is used in combination therapy for HER2-positive breast cancer. It is used for the treatment of patients with advanced or metastatic breast cancer whose tumors overexpress HER2 (ErbB2).
Triplatin tetranitrate is a platinum-based cytotoxic drug that underwent clinical trials for the treatment of human cancer. The drug acts by forming adducts with cellular DNA, preventing DNA transcription and replication, thereby inducing apoptosis. Other platinum-containing anticancer drugs include cisplatin, carboplatin, and oxaliplatin.
Magnetic-targeted carriers, also known as MTCs or magnetic vehicles, are micro- or nanoparticles that carry an anticancer drug to the target site by using an external magnetic field and field gradient to direct the desired drug. Usually the complex involves microscopic beads of activated carbon, which bind the anticancer drug. A magnet applied from outside the body then can direct the drug to the tumor site. This can keep a larger dose of the drug at the tumor site for a longer period of time, and help protect healthy tissue from the side effects of chemotherapy.
Nedaplatin is a platinum-based antineoplastic drug which is used for cancer chemotherapy. The complex consists of two ammine ligands and the dianion derived from glycolic acid.
Carmofur (INN) or HCFU (1-hexylcarbamoyl-5-fluorouracil) is a pyrimidine analogue used as an antineoplastic agent. It is a derivative of fluorouracil, being a lypophilic-masked analog of 5-FU that can be administered orally.
In oncology, the fact that one round of chemotherapy does not kill all the cells in a tumor is a poorly understood phenomenon called fractional kill, or fractional cell kill.
Antibody-drug conjugates or ADCs are an important class of highly potent biopharmaceutical drugs designed as a targeted therapy for the treatment of people with cancer. Unlike chemotherapy, ADCs are intended to target and kill only the cancer cells and spare healthy cells. ADCs are complex molecules composed of an antibody linked to a biologically active cytotoxic (anticancer) payload or drug. Antibody-drug conjugates are examples of bioconjugates and immunoconjugates.
HU-331 is a quinone anticarcinogenic drug synthesized from cannabidiol, a cannabinoid in the Cannabis sativa plant. It showed a great efficacy against oncogenic human cells. HU-331 does not cause arrest in cell cycle, cell apoptosis or caspase activation. HU-331 inhibits DNA topoisomerase II even at nanomolar concentrations, but has shown a negligible effect on the action of DNA topoisomerase I. The cannabinoid quinone HU-331 is a very specific inhibitor of topoisomerase II, compared with most known anticancer quinones. One of the main objectives of these studies is the development of a new quinone derived compound that produces anti-neoplastic activity while maintaining low toxicity at therapeutic doses.
Tubulin inhibitors are drugs that interfere directly with the tubulin system, which is in contrast to those drugs acting on DNA for cancer chemotherapy. Microtubules play an important role in eukaryotic cells. Alpha- and beta-tubulin, the main components of microtubules, have gained considerable interest because of their function and biophysical properties and has become the subject of intense study. The addition of tubulin ligands can affect microtubule stability and function, including mitosis, cell motion and intracellular organelle transport. Tubulin binding molecules have generated significant interest after the introduction of the taxanes into clinical oncology and the general use of the vinca alkaloids. These compounds inhibit cell mitosis by binding to the protein tubulin in the mitotic spindle and preventing polymerization or depolymerization into the microtubules. This mode of action is also shared with another natural agent called colchicine.
Platinum-based antineoplastic drugs are chemotherapeutic agents used to treat cancer. They are coordination complexes of platinum. These drugs are used to treat almost half of people receiving chemotherapy for cancer. In this form of chemotherapy, popular drugs include cisplatin, oxaliplatin, and carboplatin, but several have been proposed or are under development. Addition of platinum-based chemotherapy drugs to chemoradiation in women with early cervical cancer seems to improve survival and reduce risk of recurrence.
Pyr1 (LIMINIB) is an organic compound composed of carbon, hydrogen, oxygen and nitrogen that inhibits the enzyme LIM kinase.
Polymer-drug conjugates are nano-medicine products under development for cancer diagnosis and treatment. There are more than 10 anticancer conjugates in clinical development. Polymer-drug conjugates are drug molecules held in polymer molecules, which act as the delivery system for the drug. Polymer drugs have passed multidrug resistance (MDR) testing and hence may become a viable treatment for endocrine-related cancers. A cocktail of pendant drugs could be delivered by water-soluble polymer platforms. The physical and chemical properties of the polymers used in polymer-drug conjugates are specially synthesized to flow through the kidneys and liver without being filtered out, allowing the drugs to be used more effectively. Traditional polymers used in polymer-drug conjugates can be degraded through enzymatic activity and acidity. Polymers are now being synthesized to be sensitive to specific enzymes that are apparent in diseased tissue. The drugs remain attached to the polymer and are not activated until the enzymes associated with the diseased tissue are present. This process significantly minimizes damage to healthy tissue.
A nanocarrier is nanomaterial being used as a transport module for another substance, such as a drug. Commonly used nanocarriers include micelles, polymers, carbon-based materials, liposomes and other substances. Nanocarriers are currently being studied for their use in drug delivery and their unique characteristics demonstrate potential use in chemotherapy.
Directed enzyme prodrug therapy (DEPT) uses enzymes artificially introduced into the body to convert Prodrugs, which have no or poor biologically activity, to the active form in the desired location within the body. Many chemotherapy drugs for cancer lack tumour specificity and the doses required to reach therapeutic levels in the tumour are often toxic to other tissues. DEPT strategies are an experimental method of reducing the systemic toxicity of a drug, by achieving high levels of the active drug only at the desired site. This article describes the variations of DEPT technology.
