One of them is called LKB1 which has been identified to be associated with some other cancers like bowel cancers as well. We have measured it using immunohistochemistry in tissue microarrays constructed from a series of older patients with primary breast cancer.
What is LKB1, molecularly?
It’s a protein or measuring a kinase called LKB1 so you can actually measure the protein. It reflects a mutation of that protein.
This particular protein is associated with diabetes?
There has been some association with the incidence of diabetes, maybe some relationship with patients treated with metformin. We haven’t got the data yet but that’s what we have found in the literature. But what we have found is we measure them in a series of patients so we would be able to correlate this marker with other markers and the clinical outcome.
What we have done is we have got a series of about 600 older patients, by older older than the age of 70, who were treated by surgery. So we constructed tissue microarrays and then measured LKB1 on the tumours. Alongside that, we also measured another series of over twenty biomarkers so we would be able to correlate a relationship between that and others. We also have long-term clinical outcome data. What we have not got at this point in time, which will be something we are hoping to do, to explore at least, is the relationship with diabetes and treatment. So we have not got those data yet but we are hoping to explore those.
What are the lessons coming out of this for doctors looking at biomarkers?
At the moment if you focus on LKB1 this is still a bit far away from the time when we could potentially use this. But potentially this could be used as a target like, for example, trastuzumab using HER2 oncoprotein and so forth. But this is a long way away. But the overall concept, or the take home message, as part of the bigger story of this is that we should pay attention to the biological characteristics of tumours which might be related to age. For example, the older the patient is, in the context of SIOG, then they might have different biological features. So we cannot ignore these things when we manage patients.
Could markers like this help with patient individualisation?
Absolutely. This is something that one of my research programmes is looking into is how to individualise patients’ care, from a biological perspective in this case, by measuring these biomarker levels in the tumours in real time for a particular patient.
