Pseudogenes in breast cancer pathogenesis and their clinical utility

Breast cancer remains as one of the leading causes of mortality and morbidity among women worldwide, underscoring the need for a better understanding of breast cancer etiopathogenesis, effective new therapeutics and clinically actionable biomarkers. Pseudogenes, traditionally seen as nonfunctional sequences of DNA, are increasingly recognized to have important functions in physiology and disease, including in various cancers. Recently accumulating and expanding body of data has emphasized the potential role of pseudogenes in multiple aspects of breast cancer pathogenesis including their function as oncogenes or tumor suppressors to influence cellular proliferation, migration, invasion, apoptosis, angiogenesis, immune modulation, and maintenance of cancer stem cell properties. Moreover, expression of many pseudogenes has been shown to correlate with patient survival parameters and clinicopathologic characteristics of the tumor, making them excellent candidates as prognostic biomarkers. Pseudogene expression can also modulate responses of breast cancer to chemotherapeutic agents and antihormonal treatments, as well as radiotherapy, indicating their potential as treatment response biomarkers. Given their functions in breast cancer biology, pseudogenes can serve as novel targets for treatment. Here, the roles of pseudogenes in breast cancer are discussed in detail.