In contrast, the resting [Ca2+]cyt of lymphoma cells from the four MCL patients was very heterogeneous: one was not statistically different from the value obtained with healthy donor B cells (139 ± 2 nM, n =3, “MCL3”), the three others were largely and significantly increased: 390 ± 7, 347 ± 13 and 243 ± 12 nM respectively for MCL patients MCL1, MCL2 and MCL4 (n = 3, p < 0.01),. Here, MCL1 is linked to mantle cell lymphoma.