CTSD and cancer: Integrative study including previous documents, functional proteome results and bioinformatics findings, nucleophosmin involved in modulating cell growth is induced in estrogen-dependent MCF-7 cell (luminal A subtype) while progression of ZR-75-1 cell (luminal B subtype) could attribute to estrogen-independent pathway where cathepsin D would affect redox regulatory protein, cytoskeleton, hormone receptors and chaperones, which in turn, promote the long-term possibility for cancer relapse.