Editing Chemotherapy (section)

== Cytotoxics and targeted therapies ==
[[Targeted therapy|Targeted therapies]] are a relatively new class of cancer drugs that can overcome many of the issues seen with the use of cytotoxics. They are divided into two groups: small molecule and antibodies. The massive toxicity seen with the use of cytotoxics is due to the lack of cell specificity of the drugs. They will kill any rapidly dividing cell, tumor or normal. Targeted therapies are designed to affect cellular proteins or processes that are utilised by the cancer cells.<ref>{{Cite journal |last1=Vanneman |first1=Matthew |last2=Dranoff |first2=Glenn |date=2012-03-22 |title=Combining Immunotherapy and Targeted Therapies in Cancer Treatment |journal=Nature Reviews. Cancer |volume=12 |issue=4 |pages=237–251 |doi=10.1038/nrc3237 |issn=1474-175X |pmc=3967236 |pmid=22437869}}</ref> This allows a high dose to cancer tissues with a relatively low dose to other tissues. Although the [[adverse effects|side effects]] are often less severe than that seen of cytotoxic chemotherapeutics, life-threatening effects can occur. Initially, the targeted therapeutics were supposed to be solely selective for one protein. Now it is clear that there is often a range of protein targets that the drug can bind. An example target for targeted therapy is the BCR-ABL1 protein produced from the [[Philadelphia chromosome]], a genetic lesion found commonly in [[chronic myelogenous leukemia]] and in some patients with [[acute lymphoblastic leukemia]]. This [[fusion protein]] has enzyme activity that can be inhibited by [[imatinib]], a [[small molecule]] drug.<ref name="pmid18297955">{{cite journal | vauthors = Gerber DE | title = Targeted therapies: a new generation of cancer treatments | journal = American Family Physician | volume = 77 | issue = 3 | pages = 311–9 | date = February 2008 | pmid = 18297955 }}</ref><ref name="pmid12360278">{{cite journal | vauthors = Allen TM | title = Ligand-targeted therapeutics in anticancer therapy | journal = Nature Reviews. Cancer | volume = 2 | issue = 10 | pages = 750–63 | date = October 2002 | pmid = 12360278 | doi = 10.1038/nrc903 | s2cid = 21014917 }}</ref><ref name="pmid19581909">{{cite journal | vauthors = Chen HX, Cleck JN | title = Adverse effects of anticancer agents that target the VEGF pathway | journal = Nature Reviews. Clinical Oncology | volume = 6 | issue = 8 | pages = 465–77 | date = August 2009 | pmid = 19581909 | doi = 10.1038/nrclinonc.2009.94 | s2cid = 30482752 | url = https://zenodo.org/record/1233504 }}</ref><ref name="pmid19104514">{{cite journal | vauthors = Zhang J, Yang PL, Gray NS | title = Targeting cancer with small molecule kinase inhibitors | journal = Nature Reviews. Cancer | volume = 9 | issue = 1 | pages = 28–39 | date = January 2009 | pmid = 19104514 | doi = 10.1038/nrc2559 | s2cid = 17934366 }}</ref>