TNFSF13B and central nervous system cancer: Despite discrepancies, there are insights that in gliomas BAFF, APRIL, TWEAK and their receptors follow a distinct expression pattern, not identical to that observed in normal brain, neurodegenerative disease, other brain tumors, or extra CNS tissues; these molecules could provide hints for the classification of these tumors to the proliferative, angiogenic or stem-like molecular subtype.