In a recent study, other surface EV signatures were investigated: for instance, p-gp−, CD34−, and phosphatidylserine-positivity, not only correlated with disease progression and treatment resistance, but often expressed on CD138− EVs, in accordance with the fact that the immature phenotype of CD138 dim MM cells represents a negative prognostic index and predicts the occurrence of drug resistance mechanisms [148]. The gene discussed is SDC1; the disease is Miyoshi myopathy.