Scottish scientists hail drug as potential cure for leukaemia

● Glasgow researchers say antibiotic could be targeted at cancer cells

An antibiotic used to treat pneumonia has been hailed as a potential new cure for leukaemia.

Doctors at Cancer Research UK’S Beatson Institute in Glasgow found that the intravenous antibiotic tigecycline, marketed as Tygacil, kills chronic myeloid leukaemia (CML) stem cells when used in conjunction with a cancergrowth blocking drug that is the standard first-line treatment of patients with the disease.

They say their study, published yesterday, demonstrates the “exciting” effectiveness of combining tigecycline with the cancer growth-blocker imatinib.

Dr Vignir Helgason, of the University of Glasgow, joint lead author of the study, said: “We were very excited to find that when we treated CML cells with both the antibiotic tigecycline and the TKI drug imatinib, CML stem cells were selectively killed. We believe that our findings provide a strong basis for testing this novel therapeutic strategy in clinical trials in order to eliminate CML stem cells and provide a cure for CML patients.”

Using cells isolated from CML patients, the researchers showed that treatment with tigecycline, an antibiotic used to treat community-acquired bacterial pneumonia and complicated skin infections, is effective in killing CML stem cells when used in combination with imatinib.

The study also showed that the novel drug combination “significantly delayed relapse” in pre-clinical models of human CML. The Glasgow doctors say they believe that the two drugs together offer a “potentially enhanced cure rate” for CML.

Chronic myeloid leukaemia (CML) is a form of blood cancer that turns normal blood stem cells into leukaemic stem cells, or CML stem cells. These cells then produce large numbers of leukaemic cells which, if left untreated, can be fatal.

At present, CML patients are treated with tyrosine kinase inhibitors, otherwise known as TKIS, such as imatinib. TKIS are effective at killing the majority of the leukaemic cells, but they do not kill the CML stem cells from which the disease arises. Additionally, the drugs are expensive and can cause serious side effects.

Professor Eyal Gottlieb, head for the Cancer Metabolism Research Unit at the Cancer Research UK Beatson Institute, said: “Our work in this study demonstrates for the first time that CML stem cells are metabolically distinct from normal blood stem cells, and this in turn provides opportunities to selectively target them.”