Table 1: A comparison between different mechanisms deregulating the Notch receptors in B-cell acute lymphoblastic leukemia (B-ALL) and in T-cell lymphoblastic leukemia (T-ALL).

GenesB-ALLT-ALL

NOTCH1No clear evidence of mutations
Upregulated [41]
Frequent activating mutations (60% of patients) [8, 44]

NOTCH2No clear evidence of mutations
Upregulated in BM-derived precursor-B ALL cells [104]
Activating mutations only in adults [45]

NOTCH3No clear evidence of mutations
Upregulated [4042]
Epigenetic modifications: hypermethylated [36]
Rare activating mutations [9]
Frequent hyperexpression [37, 46]
Epigenetic modifications: hypomethylated or unmethylated [37]

NOTCH4No clear evidence of mutations
Upregulated [40, 41]
No clear evidence of mutations or hyperexpression

BM: bone marrow.