AKT1 and pancreatic insulinoma: However, when we compared the expression patterns of total Akt and p-Akt proteins in human insulinomas with their respective normal surrounding tissues, we found that normal islet cells showed higher or similar expression of total Akt than insulinoma cells (20/24, 83.3%) (Wilcoxon signed-rank test, p = 0.073); surprisingly, insulinoma cells showed markedly lower p-Akt staining than their surrounding normal islet cells in 21/24 tumors (87.5%) (Wilcoxon signed-rank test, p = 0.002) (Figures 2(b)–2(d) and 3).