Network-based analysis of prostate cancer cell lines reveals novel marker gene candidates associated with radioresistance and patient relapse
Fig 5
Marker gene-based separation of irradiated prostate cancer patients into early and late relapse groups.
Potential radioresistance driver genes revealed from DU145 (top and middle row) and LNCaP (bottom row) were analyzed for their expression behavior in 32 irradiated prostate cancer patients from TCGA. Expression levels of each marker gene across the 32 patients were used to determine a marker gene-specific optimal cutoff for disease-free survival risk curves separating patients with low (blue curve) and high (red curve) marker gene expression with respect to the constraint that at least 8 patients must be assigned to each curve. Log-rank test p-values indicate that these selected marker genes enable a separation of irradiated prostate cancer patients into early and late relapse groups. Shown are standard approximate log-rank test p-values that only marginally deviated from exact log-rank p-values determined by exhaustive computations, except for FOXL1 that had a clearly less significant exact log-rank p-value of 0.076 (see Methods for details and S4 Fig). See S1 Text for a detailed discussion of the driver candidates in the context of the existing literature.