STAT3 and AL amyloidosis: Indeed, there are alternative signaling pathways that have been shown to be important in causing drug resistance, such as aberrant, constitutively active PI3K/Akt-mediated signaling in AML, and over-expression of Cdc28 protein kinase regulatory subunit 1B (CKS1B), which leads to activation of Jak/STAT3 and MEK/ERK signaling pathways in multiple myeloma [34], [35].