APOA1 and urinary bladder cancer: Although lipoproteins are believed to likely indirectly promote tumor survival or increase tumor angiogenesis, the relationship between the changes in the lipoprotein levels, apoA1 with bladder cancer progression, and disparity in the lipoprotein-related proteome between bladder tissue and urine is still uncertain, and necessitates further investigation in order to understand its potential as a biomarker.