Furthermore, upregulated Sox2 mRNA expression in Ptenfl/flArid1afl/fl tumours is consistent with a less differentiated phenotype, while we found no evidence of neuro-endocrine differentiation with reduced SYP (Synaptophysin) and equivocal CHGA (Chromogranin A) mRNA expression (Fig. 2e). The gene discussed is CHGA; the disease is neoplasm.