S100A4 and neoplasm: In 2021, our team established the first CAF tumor cell line, HXWMF-1 (α-SMA, vimentin, HSP47, S100A4/FSP1, FAP, PDGFRβ, and CD34 positive) (147), originated from the subcutaneous xenografts of HXEX-ALL1 (148), a cell line from a relapsed patient with B-ALL.