NES and cancer: Nestin was initially discovered based on its expression in neural progenitor cells, where it was considered a marker for distinguishing precursor cells from differentiated cells.[29, 30] Subsequent reports have shown that nestin is expressed in breast, prostate and pancreatic cancer, and is positively correlated with tumor malignancy.[31-33] But some findings regarding nestin are inconclusive or controversial, especially in the context of cancer staging.