STAT3 and AL amyloidosis: Abnormal elevated STAT3 activity has been found in a variety of hematological and solid malignancies such as acute myeloid leukemia (AML), multiple myeloma, and cancers of the bladder, head and neck, kidney, pancreas, uterus, ovary, esophagus, and breast (Chen et al., 2008; Sahu and Srivastava, 2009; Bar-Natan et al., 2012; Li et al., 2013; Suh et al., 2015; Geiger et al., 2016; Subramaniam et al., 2016; Zhang et al., 2016).