giving men a better chance of beating prostate cancer
Dr Guy Simpson
Optimal cancer therapy leading to a cure has not been achieved in all tumour types. The best
strategies for new treatment remain to be defined, but we need to look beyond traditional
chemotherapy and radiotherapy.
Our laboratory has an interest in so called “oncolytic viruses” or cancer killing viruses. The
idea behind the concept of oncolytic viruses is best illustrated by the case of an 8 year old boy with
Burkitt’s Lymphoma (solid tumour). Then he became infected with measles virus, after which the
tumour went away. This case shows us that oncolytic viruses are able to grow in and kill tumours.
For many years I have had an interest in developing viruses as a treatment for cancer. In the past
I have helped develop a herpes simplex virus that has gone through all three phases of clinical
trials becoming this year the first, so called “ oncolytic virus “ or cancer killing viruses to show
efficacy in patients. Both herpes simplex virus (HSV) and reovirus is able to replicate within tumour cells and not in normal healthy cells of the body due to a specific mutation of a gene common to many cancers. As the virus replicates within the tumour cells new viral offspring are produced. These burst out of the cell causing the tumour cell to burst and die.
In this last year I have worked on a cold related virus called Coxsackie virus which is currently in phase I-II clinical trials for melamona (skin cancer). We have shown that:
• Coxsackie virus can grow in and kill bladder cancer cells.
• Combination of Coxsackie virus with either chemotherapy or radiotherapy shows enhanced tumour killing compared to either anti-cancer agent alone.
• My work has shown that chemotherapy or radiotherapy improves the ability of the virus to enter tumours cells through entry molecules.
• Further work has shown that cancer cells infected with Coxsackie virus express molecules called Immune Death Markers that suggest that this treatment will produce a strong anti-cancer vaccine response. Based on this work a phase I clinical trial has started on non-muscle invasive bladder cancer. This is a first in- man clinical trial.