ENPP1 and Miyoshi myopathy: The BM niche contains cells expressing different ectoenzymes (one of the richest conglomerates of such molecules): out of these, relevant is ectonucleotide pyrophosphatase/phosphodiesterase-1 (ENPP1), a molecule also known as plasma cell-1 (PC-1), the first marker identified on MM cells (now CD203a) [48].