Role of PHB2 as a potential biomarker in pan-cancer: a multi-database analysis

Prohibitin2 (PHB2) is a mitochondrial endosomal protein that is closely linked to tumors; however, its specific molecular role remains unclear. Therefore, this study investigates the role of PHB2 in cancer. Multiple databases, including cBioPortal, PhosphoNET, and AlphaFold, were accessed to investigate this issue. The findings indicated that PHB2 expression in tumor tissues exceeded that in normal tissues, with PHB2 localized in mitochondria. Patients diagnosed with bladder and lung adenocarcinomas exhibiting elevated PHB2 expression demonstrated an increased survival rate compared to those with reduced expression levels. Conversely, the opposite was observed in patients with renal clear cell carcinoma and breast cancer. In pan-cancer, the mutation rate of PHB2 was elevated, with several overlapping amino acid sites exhibiting tumor mutations and post-translational modifications, including phosphorylation at tyrosine 121, acetylation at threonine 263, and ubiquitination at lysine 296. Multiple overlapping sites of amino acid phosphorylation modifications and mutations were identified in PHB2, specifically at threonine 42, tyrosine 121, and threonine 263. The three-dimensional predicted structure of PHB2 was analyzed utilizing the AlphaFold database. The pathogenicity mutation heatmap indicated that the overlapping sites of amino acid mutations and post-translational modifications, including phosphorylation (threonine 42, tyrosine 121, and threonine 263), acetylation, and ubiquitination (lysine 296), were significantly pathogenic. In conclusion, PHB2 exhibits cancer-type-specific prognostic associations. Its overlapping mutation and modification sites suggest potential functional importance, supporting its role as a candidate biomarker for further validation in pan-cancer contexts.