Researchers at the University of Edinburgh in Scotland have built a mathematical model to determine the role of PTEN protein expression on resistance to trastuzumab(Drug information on trastuzumab) (Herceptin).
Dana Faratian, MD, and colleagues used 56 differential equations to analyze the change in concentrations of 56 separate biological entities including proteins and lipid second messengers.
They worked with 122 breast cancers treated with trastuzumab and found that quantitative PTEN protein expression was a key determinant of who would be resistant or sensitive to trastuzumab. In addition, using the mathematical modeling techniques, the absence of PTEN was more predictive than could be determined using standard multivariate or laboratory analysis (Cancer Res online, July 21, 2009).
The results help explain why some patients still fail on tratuzumab, commented Sofia Merajver, MD, PhD, a Cancer Research editoral board member.