In addition to its diverse roles in normal cells, aberrant GPNMB/OA expression has been linked to various pathological disorders such as glaucoma [10], kidney disease [11], osteoarthritis [12] and several types of cancer, including: uveal melanoma [13], glioma [14], [15], hepatocellular carcinoma [16] and cutaneous melanoma [17]. This evidence concerns the gene GPNMB and osteoarthritis.