In agreement with higher tumor burden by BTK-KD MM cells in vivo was the overexpression of MM-associated markers such as SDC1 and CLK2 and heparanase target gene, PLXNC1. 27,28 Additional upregulated genes, such as ADA, negatively regulate leukocyte migration (Figure 5c). Here, SDC1 is linked to Miyoshi myopathy.