One of the many problems with cancer is it’s ability to cloak itself from the body’s immune system. White blood cells, specifically T-lymphocytes or ‘T-cells’, should recognise foreign material in the body and destroy it. But the tumour has evolved to cloak itself from the t-cells by producing a surface molecule called Ligand. The Ligand fuses with receptors of the T-cells known as PD-1. The receptor is activated and so the T-cells treat the tumour as safe, thus the tumour has fooled the immune system. But if you can stop the interaction between the Ligand and PD-1 then then the immune system should act to destroy the tumour.
In recent research on 135 people with melanoma, 54 of those had their tumour more than halve in volume when treated with the antibody Lambrolizumab. 57 of the 135 people were given very high doses of the drug and 6 of these people their tumours were eradicated.
With a second antibody, Nivolumab, the tumours more than halved in volume for 21 out of 53 people.
With a third antibody it targeted the Ligand molecule rather than the PD-1 receptor. This also produces impressive results for other types of cancer including lung and kidney cancer.
One of the researchers, Jedd Wolchok of the Memorial-Sloan Kettering Cancer Centre New York, said ‘They [the remedy] treat the patient, not the tumour.’ I think this is looking like a promising start to what might be the future of curative care for cancer sufferers.