PROM1 and familial pancreatic carcinoma: In agreement with this hypothesis, overexpressing FAM83A in pancreatic cancer cells markedly increased the CD133+ population (Figures 2b and c), which is exclusively tumorigenic and highly chemoresistant.12 Moreover, FAM83A-transduced cells formed significantly larger and higher numbers of spheres in the tumorsphere formation assay compared with vector control cells (Figure 2d).