SOSTDC1 and AL amyloidosis: Furthermore, in the 5T2MM murine model of multiple myeloma (MM), Sostdc1 was shown to be expressed in low levels in MM and OB lineage cells while these cells were separately cultured, but its expression was substantially also induced in cell types when they were co-cultured, suggesting that the expression of Sostdc1 in 5TGM1-infiltrated bones could suppress osteoblast differentiation in bone and tumor microenvironment (Faraahi et al., 2019).