The role of molecular biology in the identification of predictive factors for prostate cancer incidence

Dr José Antonio López - Instituto Valenciano de Oncología, Valencia, Spain

It was since six years ago because in 2005 the group discovered a new fusion gene in prostate cancer and we see the opportunity to ask for a grant to the national government in order to investigate the prognostic implications of this molecular alteration in prostate cancer. And fortunately we received this grant and since then we established a line of investigation in prostate cancer.

Why do we need a prognostic factor in prostate cancer?

Because we need to select patients for better management, clinical management, in order to define very well the diagnosis of prostate cancer. Because, if you know, prostate cancer has a problem from the diagnostic point of view because we cannot distinguish between those cancers with a better outcome from those with a worse prognosis. It leads to over-diagnosis and overtreatment in prostate cancer so what we need is to identify specifically prostate cancer and from those prostate cancers which cancers are aggressive from indolent.

Indolent prostate cancers may not need to be treated?

They need to be followed not treated. So there are clinical protocols that are called active surveillance in order to follow these patients with these tumours, low grade tumours, not aggressive and they don’t need any treatment. But it is convenient to follow these patients because the tumour can change and progress.

What sorts of signals are you getting from your tests?

Mainly the different molecular characteristics of the tumour, the histological examination with the Gleason score. Those cancers with a high Gleason score must be treated by surgery or by radiotherapy but we know that prostate cancer is a heterogeneous disease from the genetic point of view and we know that depending on these molecular features the behaviour of the prostate cancer is completely different.

Have you got a signature that will predict aggressive disease?

There is not any specific. We don’t select patients according to their molecular signature. We have information about the behaviour of different tumours depending on the biotype, of a molecular signature, but we don’t treat according to this feature at the moment. We hope that in the future, in two or three years, we can treat cancer according to a specific biotype.

Might some of these signatures be a clue to vaccination and prevention in future?

It can change the means of how to manage the prostate cancer. I think if we identify those patients with a tumour with a particular characteristic we can prevent the progression of this tumour.

Do you think a better screening test is possible from your work?

Yes, I think that we can improve the accuracy of PSA incorporating additional biomarkers to the diagnosis, in the diagnostic setting. For instance, there are a lot of biomarkers now in the market: PCA3, for instance, that is a biomarker that is emitted in the urine of patients and it improves the detection of prostate cancer with high PSA levels. So I think that it is the way. The future is working with the panel biomarkers for detecting prostate cancer.