As shown by representative IHC images in Fig. 7A, both CNOT2/9 and SHMT1 were overlapped with CK19, the marker of epithelial cells (Fig. 7A, images N, R, and V), but not with TdT, the marker of immature lymphocytes (Fig. 7A, image J), indicating that CNOT2/9 and SHMT1 were highly expressed in the epithelia in thymoma samples, but not in the epithelia of TSCC. Here, SHMT1 is linked to thymoma.