Background

SPARC (secreted protein acid rich in cysteine) belongs to a group of extracellular matrix proteins and promotes adhesion of cells to the matrix. As such, expression of this protein plays an important role in tumor development in breast cancer and has a significant bearing on patient prognosis and long term survival. It is also known to predict response to nab-paclitaxel in certain tumor types including breast cancer. In 2005, the FDA approved a solvent free formulation of paclitaxel for the treatment of metastatic breast cancer that utilizes albumin bound (nab) technology (Abraxane; nab-paclitaxel). Clinical studies have shown that nab-paclitaxel is significantly more effective than paclitaxel. Our study was designed to evaluate the frequency distribution of SPARC among breast cancer patients with a special emphasis on triple negative patients in which identification of a novel therapeutic target is warranted.