Are there significant differences in proteins from normal vs. diseased tissues and/or between patients?
There exists a large potential bias in specific protein expression profiles due to tissue heterogeneity in and between normal and diseased tissue from different human patients. For example, tumor activity and structure can vary significantly between patients even though the cancers are classified and may be graded identically. Additionally, extraction conditions are not necessarily optimized for enrichment of proteins from specific families or classes. Instead, a widely accepted set of buffers is employed to fractionate soluble (modified RIPA buffer) and insoluble (Urea-based buffer) proteins. Expect some variation from materials prepared from different patients.
