Table 1.

Growth response of T-cell acute lymphoblastic leukaemia (T-ALL) cells to MEK inhibition

	Co-culture with
	MS5 cells		MS5-DL1 cells
T-ALL samples	Diluent	MEKi	Diluent	MEKi
M18	0	+++	+	++
M18 x	++	++++	+++	++++
M22	0	++	0	++
M30	+	++	++	+++
M34	0	+	+++	+++
M40	0	+	+	++
M69 x	++	+++	+++	+++
M78 x	++	+++	+++	+++
M86	0	+	0	+
M97	+	++	+++	++++
M105	+++++	+++++	+++++	+++++
M105 x	++++	++++	+++	nd
M106 x	+++	++++	++++	++++
M108	++++	+++++	nd	nd
M109	0	0	+	++
M110	0	+	nd	nd
M112 x	+	+	nd	nd
M114	+++	++	+++	nd
M118	0	+	+++	nd
M120	+	++	nd	nd
M121	0	0	+	+
M129 x	+++	+++	+++	nd

Human T-ALL cells isolated from newly diagnosed patients or from xenografted mice (x) were seeded (2 × 10⁵/well in 24-well plates) on MS5 or MS5-DL1 stromal cells and cultured in the presence of MEKi (1 μM PD184352) or diluent alone (DMSO, negative control) for 28 days. CD45+CD7+ leukaemic cells were counted at day 28 and (+), (++), (+++), (++++), (+++++) indicate, respectively, a < 10-fold, between 10- and 50-fold, 50- and 250-fold, 250- and 1,000-fold and higher than 1,000-fold number increase compared to the original number of seeded cells. 0, no cells were recovered after culture; nd, not done.