It has been reported that TRPV1 is expressed not only in small neurons but also in medium to large neurons, and upregulated TRPV1 in bone cancer mouse DRG neurons mainly occur in calcitonin gene–related peptide–positive peptidergic neurons and neurofilament 200–positive myelinated neurons (9), which have previously been implicated in mechanical allodynia (57–59). This evidence concerns the gene TRPV1 and bone neoplasm.