HSP90AB1 and varicocele: Proteins associated with acetylation involved in fertilization and acrosome reaction (transaldolase 1 [TALDO1], histone cluster 1 H2B family member B [HIST1H2B], and glucosamine-6-phosphate deaminase 1 [GNPDA1]), apoptosis and DNA damage (heat shock protein HSP 90-beta [HSP90AB1], serine/threonine-protein phosphatase 5 [PPP5C], and RuvB-like 2 [RUVBL2]), and mitochondrial dysfunction (succinate dehydrogenase complex flavoprotein subunit A [SDHA], peroxiredoxin-1 [PRDX1], and glutathione reductase [GSR]) have been proposed as post-translational protein biomarkers in varicocele patients [45].