Prostate cancer is the most common type of cancer, and there is a pressing demand for both prognostic and predictive biomarkers. Despite massive and long-lasting efforts, cancer researchers have not yet succeeded. Research from the group proves that the presence of multiple tumour foci with different molecular characteristics complicates the development of biomarkers, in particular if this inter-focal heterogeneity is not taken into account.
By utilizing a multifocality oriented biobank, the research group has recently demonstrated that individual tumour foci from the same patient have completely separate sets of somatic mutations (Løvf et al., 2019). Furthermore, expression of RNA-biomarkers show similar inter-focal heterogeneity, and altogether this challenges the clinical usefulness of molecular classification of primary prostate cancer (Carm et al., 2019). Thus, introduction of genomics-guided personalized medicine has to take information from all tumour foci into account. This is a challenging task when it comes to sampling from the patients. To overcome this, the research group studies how this heterogeneity can be recapitulated in liquid biopsies (the cell free DNA [cfDNA] fraction of plasma). Also, for monitoring of prostate cancer, the group now tests whether mutation detection from cfDNA can inform on which of the original tumour foci that caused the disease relapse. The idea is that this can inform back to the primary situation, to enable development of improved prognostic biomarkers which will be informative for future patients with localized prostate cancer.
Carm KT, Hoff AM, Bakken AC, Axcrona U, Axcrona K, Lothe RA, Skotheim RI*, and Løvf M (2019). The clinical usefulness of molecular classification of primary prostate cancer is challenged by interfocal heterogeneity. Scientific Reports 9: 13579 *Corresponding author
Løvf M, Zhao S, Axcrona U, Johannessen B, Bakken AC, Carm KT, Hoff AM, Myklebost O, Meza-Zepeda LA, Lie AK, Axcrona K, Lothe RA, and Skotheim RI (2019). Multifocal primary prostate cancer exhibits high degree of genomic heterogeneity. European Urology, 75(3): 498-505