TAs were constructed in our laboratory using a manual tissue arrayer (MTA1, Beechers Instruments, Sun Prairie, WI, USA) as described in detail elsewhere (Nariculam et al. 2009 (link); Symes et al. 2013 (link)). Individual tissue cores (1 mm diameter) were extracted from the marked regions of prostate cancer and cancer adjacent (normal) prostate tissue blocks and moved to a recipient block using a Beechers MTA1 manual tissue arrayer (Beechers Instruments, Sun Prairie, WI, USA). Five recipient blocks were populated with samples (five to six tissue samples) from both prostate cancer (N = 29, n = 91) and cancer adjacent region (N = 29; n = 67) of the whole tissue blocks (N = number of patients, n = number of cores). Each individual tissue core was also examined by uropathologist to assess the Gleason grades (Supplementary Table 1). The following distribution of Gleason grades were used: 3 + 3 (n = 15); 3 + 4 (n = 4); 4 + 3 (n = 11); 4 + 4 (n = 43); 4 + 5/5 + 4 (n = 22).
TA blocks were sectioned at 6–8 μm thickness on glass slides using a Thermo Scientific™ HM355S automatic microtome. Sections on slides were stained with hematoxylin and eosin (H&E) and imaged at 40× magnification using NanoZoomer Digital Pathology Scanner 2.0 RS (Hamamatsu, Hertfordshire, UK) and re-examined by the pathologist.
TA blocks were sectioned at 6–8 μm thickness on glass slides using a Thermo Scientific™ HM355S automatic microtome. Sections on slides were stained with hematoxylin and eosin (H&E) and imaged at 40× magnification using NanoZoomer Digital Pathology Scanner 2.0 RS (Hamamatsu, Hertfordshire, UK) and re-examined by the pathologist.