TFE3 and neoplasm: Immunohistochemical staining exhibited nuclear or nuclear/cytoplasmic TFE3 staining in the tumor cells from BHD patients (Fig. 4B and S2B) although the intensity was not as strong as in the t(X;1)(p11.2;q21) translocation alveolar soft part sarcoma involving TFE3 (Fig. S2B).