Figure 1.

SDHB protein expression and enzymatic activity are altered in missense/nonsense mutation-associated tumor tissue. A) Immunohistochemical staining for SDHB in tumor tissue with missense (ΔSDHB-R11H) and nonsense (ΔSDHB-T115X) mutations. B) Western blot of the SDHB protein in microdissected PHEOs and PGLs associated with mutations in the SDHB, MEN1, or VHL genes. C) Quantification of the SDHB protein in microdissected tumor tissue (n=3 for each type of tumor). D) Real-time-PCR quantification of SDHB mRNA transcription in microdissected tumors (n=4; 3 technical replicates for each sample). Normal adrenal tissue (NAM) was used as a positive control. E) SDHB enzyme activity of tumor samples with SDHB gene nonsense or missense mutations (n=6; 3 technical replicates for each sample). NAM was used as a positive control.