These results suggested that FAM46C might be involved in PC differentiation, so we first quantified FAM46C mRNA levels by qRT‐PCR in four BC populations, immature, naïve, memory B cells and PCs isolated from BM samples obtained from healthy donors.35FAM46C expression was significantly higher in PCs than in the earlier stages of differentiation (Figure 6A, left panel) and was similar in PCs and in HMCLs (Figure 6A, right panel). This evidence concerns the gene TENT5C and breast cancer.