In recent years, scientists have realised the role bacteria can play in cancer growth and resistance to chemotherapy drugs – but these tiny microbes could prove useful in treating the disease, too. Abi Millar examines the promises and limitations of therapeutic bacteria an as approach to treating cancer.
In the late 19th century, an American bone surgeon named William Coley discovered a surprising pattern: cancer patients who also developed skin infections seemed to be getting better. Reviewing the research, he had found dozens of cases confirming his hunch that bacteria might be involved in tumour regression.
While Coley did not fully understand the mechanism responsible – an immune response –he felt this was an avenue worth pursuing. He began to treat his own cancer patients with streptococcus bacteria, injected straight into the tumour site. Many patients recovered, but others died, prompting Coley to use inactivated bacteria instead.
Today, after many decades in which his ideas went undeveloped, Coley is considered the ‘father of cancer immunotherapy’. And while his treatment was neither safe nor especially effective, ‘Coley’s toxins’ are a precursor to a wave of bacteria-based cancer therapies being explored today.
Read the rest of this article in the October 2021 edition of Pharma Technology Focus