Rrapaj E, et al. - Using biopsy samples from patients with malignant pleural mesothelioma (MPM) via immunohistochemistry and reverse transcription–polymerase chain reaction (RT–PCR), authors attempted to examine high mobility group box 1 (HMGB1) protein and gene expression. Yielded data displayed that HMGB1 could be a useful prognostic biomarker in MPM when detected by immunohistochemistry. Since it was also expressed in normal and reactive mesothelial cells, HMGB1 could not serve as a diagnostic biomarker in histological samples of mesothelioma.