Targeted therapy

Targeted therapy

Targeted therapy is a type of medication that blocks the growth of cancer cells by interfering with specific targeted molecules needed for carcinogenesis and tumor growth, rather than by simply interfering with rapidly dividing cells. Targeted cancer therapies may be more effective than current treatments and less harmful to normal cells.

The main categories of targeted therapy are "small molecules" and "monoclonal antibodies."

mall molecules

*Imatinib mesylate (Gleevec, also known as STI–571) is approved for chronic myelogenous leukemia, gastrointestinal stromal tumor and some other types of cancer. Early clinical trials indicate that imatinib may be effective in treatment of dermatofibrosarcoma protuberans.
*Gefitinib (Iressa, also known as ZD1839), targets the epidermal growth factor receptor (EGFR) tyrosine kinase and is approved in the U.S. for non small cell lung cancer. EGFR is also overexpressed in the cells of other solid tumors, such as lung and breast cancers. This leads to inappropriate activation of the apoptotic Ras signal transduction cascade, eventually leading to uncontrolled cell proliferation.Gefitinib inhibits EGFR tyrosine kinase by binding to the adenosine triphosphate (ATP)-binding site of the enzyme. Thus the function of the EGFR tyrosine kinase in activating the Ras signal transduction cascade is inhibited; and malignant cells are inhibited.
*Erlotinib (marketed as Tarceva). Erlotinib works through a similar mechanism as gefitinib. Erlotinib has been shown to increase survival in metastatic non small cell lung cancer when used as second line therapy. Because of this finding, erlotinib has replaced gefitinib in this setting.
*Bortezomib (Velcade) is an apoptosis-inducing drug that causes cancer cells to undergo cell death by interfering with proteins. It is approved in the U.S. to treat multiple myeloma that has not responded to other treatments.

Monoclonal antibodies

Several are in development and a few have been licenced by the FDA. Examples of licenced monoclonal antibodies include:
*Rituximab targets CD20 found on B cells. It is used in non Hodgkin lymphoma
*Trastuzumab (Herceptin) targets the Her2/neu (also known as ErbB2) receptor expressed in some types of breast cancer
*Cetuximab (marketed as Erbitux) targets the epidermal growth factor receptor. It is used in the treatment of colon cancer and non-small cell lung cancer.
*Bevacizumab (marketed as Avastin) targets circulating VEGF ligand. It is approved for use in the treatment of colon cancer, breast cancer, non-small cell lung cancer and is investigational in the treatment of sarcoma.

Progress and future

Many oncologists believe that targeted therapies are the chemotherapy of the future. As solid tumor cancer continues to be viewed as a chronic condition, methods for long-term treatment, with less side-effects, continue to be investigated.

In the U.S., the National Cancer Institute's " [http://home.ncifcrf.gov/mtdp Molecular Targets Development Program] " (MTDP) to identify and evaluate molecular targets that may be candidates for drug development.

The next stage of targeted therapies will focus on finding which patients will respond to which targeted therapies. This is called the identification of "sub-populations". The route to identify these sub-populations is through biomarkers and surrogate endpoints.

One agent which seems to be promising is cannabidiol, a non-toxic substance found in cannabis which has been found to reduce growth and invasiveness of cancer cells in vitro.

References

*Green, Mark [http://content.nejm.org/cgi/content/full/350/21/2191 "Targeting Targeted Therapy"] New England Journal of Medicine (May 20, 2004)
* [http://www.jco.org/content/vol23/issue11/ "Molecular Oncology: Receptor-Based Therapy"] Journal of Clinical Oncology (April 10, 2005)
*Lynch, Thomas [http://content.nejm.org/cgi/content/full/350/21/2129 "Activating Mutations in the Epidermal Growth Factor Receptor Underlying Responsiveness of Non–Small-Cell Lung Cancer to Gefitinib"] New England Journal of Medicine (May 20, 2004)

ee also

* [http://www.targetedtherapies.org/index.html?52831101.13431698 Advances in Targeted Cancer Therapies]
* [http://www.cancer.gov/cancertopics/factsheet/Therapy/targeted National Cancer Institute Fact Sheet]


Wikimedia Foundation. 2010.

Игры ⚽ Нужна курсовая?

Look at other dictionaries:

  • Targeted therapy — Die gezielte Krebstherapie (engl. targeted therapy ) ist ein neuer Ansatz in der Behandlung von Krebs. Dank neuer Erkenntnisse der Molekularbiologie und Biomedizin können in der gezielten Krebstherapie bestimmte Merkmale und Eigenschaften… …   Deutsch Wikipedia

  • targeted therapy — A type of treatment that uses drugs or other substances, such as monoclonal antibodies, to identify and attack specific cancer cells without harming normal cells …   English dictionary of cancer terms

  • molecularly targeted therapy — chemotherapy with molecularly targeted agents …   Medical dictionary

  • Targeted drug delivery — Targeted drug delivery, sometimes called smart drug delivery,[1] is a method of delivering medication to a patient in a manner that increases the concentration of the medication in some parts of the body relative to others. The goal of a targeted …   Wikipedia

  • B-cell–targeted therapy — a type of immunotherapy that decreases the immune response caused by B lymphocytes, using monoclonal antibodies for treatment of autoimmune conditions …   Medical dictionary

  • molecularly targeted therapy — In cancer treatment, substances that kill cancer cells by targeting key molecules involved in cancer cell growth …   English dictionary of cancer terms

  • Radiation therapy — Radiation (medicine) redirects here. It is not to be confused with Radiation (pain) or Radiology. Radiation therapy Intervention ICD 10 PCS D ICD 9 CM …   Wikipedia

  • Antisense therapy — is a form of treatment for genetic disorders or infections.When the genetic sequence of a particular gene is known to be causative of a particular disease, it is possible to synthesize a strand of nucleic acid (DNA, RNA or a chemical analogue)… …   Wikipedia

  • Hormonal therapy (oncology) — Hormonal therapy is one of the major modalities of medical treatment for cancer, others being cytotoxic chemotherapy and targeted therapy (biotherapeutics). It involves the manipulation of the endocrine system through exogenous administration of… …   Wikipedia

  • viral therapy — Treatment using a virus that has been changed in the laboratory to find and destroy cancer cells without harming healthy cells. It is a type of targeted therapy. Also called virotherapy and oncolytic virotherapy …   English dictionary of cancer terms

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”