Proteinuria is pathogenic to proximal tubular cells (PTC) and linked with progression to renal failure. The aim of this study was to determine the effects of human serum albumin (HSA) overload on the changes in gene and protein expression stimulated by oxidative stress in PTC and any interaction with Angiotensin II (AngII) that is pivotal in disease pathogenesis. Markers of oxidative stress, antioxidant defences, transcription factor activation, and the expression of stress-related genes were measured in human PTC (HK-2 cells) overloaded with either globulin-free fatty acid free (GF/FAF) HSA or globulin-free (GF) HSA. The effects of AngII were also determined. HSA overload in HK-2 cells caused PTC hyperfunction, increased oxidative stress and an upregulation of adaptive responses and stress-related genes. Some responses were common to both HSAs but others were unique to either HSA, and unaffected by addition of AngII or Candesartan (a specific AngII type 1 receptor blocker). AngII also independently induced oxidative stress and up-regulated other stress-related genes. HSA overload in HK-2 cells stimulated increased oxidative stress and upregulated changes in stress-related gene expression indicating new pathways of PTC injury that are not mediated via AngII type 1 receptors.