IRS1 and acute lymphoblastic leukemia: Similarly, lower levels of expression of P-IGF-1R (Tyr1131) and P-IRS-1 (Ser794) were detected in the Bp-ALL REH [t(12;21)] and SupB15 [t(9;22)] subtypes characterized by non-random translocations in comparison to NALM6 (Fig. 5B).