However, in a context of comorbidity between psoriasis and OP, and shared pathophysiological mechanisms such as vitamin D deficiency and inflammatory pathways (particularly RANKL-mediated), the IL-33/ST2 axis exhibits a paradoxical effect, shifting from an osteoprotective to a proinflammatory and osteoclastogenic role, thereby driving the development of OP. The gene discussed is TNFSF11; the disease is vitamin D deficiency.