SLC34A1 and acute myeloid leukemia: Spindle cells in allograft AML tumours (Fig. 3e) also expressed the proximal tubule marker protein NAPI2A and epithelial structures in these tumours were positive for the epithelial markers E-CADHERIN and PAN-CYTOKERATIN and stained positively for pan-CD133, RCC and CD10 (Fig. 3e), three markers of the renal proximal tubule epithelium.