Editing Experimental cancer treatment (section)

==Bacterial treatments==
[[Chemotherapy|Chemotherapeutic]] [[medication|drugs]] have a hard time penetrating tumors to kill them at their core because these cells may lack a good blood supply.<ref>{{Cite journal |last1=Boohaker |first1=R. J. |last2=Lee |first2=M. W. |last3=Vishnubhotla |first3=P. |last4=Perez |first4=J. L. M. |last5=Khaled |first5=A. R. |title=The Use of Therapeutic Peptides to Target and to Kill Cancer Cells |url=https://www.eurekaselect.com/article/44099 |journal=Current Medicinal Chemistry |date=2012 |language=en |volume=19 |issue=22 |pages=3794–3804 |doi=10.2174/092986712801661004 |pmc=4537071 |pmid=22725698}}</ref> Researchers have been using [[anaerobic bacteria]], such as ''[[Clostridium novyi]]'', to consume the interior of oxygen-poor tumours. These should then die when they come in contact with the tumor's oxygenated sides, meaning they would be harmless to the rest of the body. A major problem has been that bacteria do not consume all parts of the malignant tissue. However, combining the therapy with chemotherapeutic treatments can help to solve this problem.

Another strategy is to use anaerobic bacteria that have been transformed with an enzyme that can convert a non-toxic [[prodrug]] into a toxic drug. With the proliferation of the bacteria in the [[necrosis|necrotic]] and [[Hypoxia (medical)|hypoxic]] areas of the tumor, the enzyme is expressed solely in the tumor. Thus, a systemically applied prodrug is metabolised to the toxic drug only in the tumor. This has been demonstrated to be effective with the nonpathogenic anaerobe ''[[Clostridium sporogenes]]''.<ref name="Mengesha">{{cite book |author= Mengesha|year=2009|chapter=Clostridia in Anti-tumor Therapy |title=Clostridia: Molecular Biology in the Post-genomic Era|publisher=Caister Academic Press|isbn =  978-1-904455-38-7  }}</ref>