MS4A1 and lung carcinoma: We found the culture supernatant of the CD20+ B cells also suppressed the growth of A549 and H1299 cells (Fig. 4b, Additional file 1: Figure S3b), indicating the effects of the CD20+ B cells on lung cancer cells can be independent of cell-cell interaction and also suggesting that the CD20+ B cell-secreted proteins might contribute to the tumor-suppressive function of CD20+ B cells in NSCLC.