Dataset Information

Src inhibitors, PP2 and dasatinib, increase retinoic acid-induced association of Lyn and c-Raf (S259) and enhance MAPK-dependent differentiation of myeloid leukemia cells.

ABSTRACT: All-trans-retinoic-acid (ATRA)-induced differentiation of human myeloid leukemia cells is characterized by persistent mitogen-activated protein kinase (MAPK) signaling. Fragmentary data suggests Src family kinase (SFK) inhibitors enhance differentiation, and thus have potential therapeutic value. The present study shows that SFK inhibitors PP2 and dasatinib enhance aspects of MAPK signaling and regulate a panel of differentiation markers, including CD11b and p47(phox). HL-60 and NB4 myeloid leukemia cells show accelerated ATRA-induced G1/0 arrest/differentiation with inhibitor co-treatment. We also identified components of a Lyn- and c-Raf-containing MAPK signaling complex augmented by the inhibitors. PP2 and dasatinib increased the ATRA-induced expression of Lyn and c-Raf (total and c-RafpS259) and their interaction. The Lyn-associated serine/threonine kinase, casein kinase II (CK2), also complexed with c-Raf and c-RafpS259, and the kinase suppressor of Ras 1 (KSR1) scaffold protein bound c-Raf, Lyn and extracellular signal-regulated kinase (ERK). c-Raf/ERK association was increased by the inhibitors, which is significant as ERK may cause c-Raf C-terminal domain (CTD) phosphorylation in a putative feedback mechanism. Consistent with this, inhibitor treatment caused more CTD phosphorylation. Lyn knockdown decreased c-Raf CTD and S259 phosphorylation. This is the first evidence suggesting SFK inhibitors enhance ATRA-induced differentiation through a possible feedback loop involving KSR1-scaffolded c-Raf and ERK complexed with Lyn and CK2.

SUBMITTER: Congleton J

PROVIDER: S-EPMC3310950 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Src inhibitors, PP2 and dasatinib, increase retinoic acid-induced association of Lyn and c-Raf (S259) and enhance MAPK-dependent differentiation of myeloid leukemia cells.

Congleton J J MacDonald R R Yen A A

Leukemia 20111219 6

All-trans-retinoic-acid (ATRA)-induced differentiation of human myeloid leukemia cells is characterized by persistent mitogen-activated protein kinase (MAPK) signaling. Fragmentary data suggests Src family kinase (SFK) inhibitors enhance differentiation, and thus have potential therapeutic value. The present study shows that SFK inhibitors PP2 and dasatinib enhance aspects of MAPK signaling and regulate a panel of differentiation markers, including CD11b and p47(phox). HL-60 and NB4 myeloid leuk ...[more]

PMID: 22182854

Similar Datasets

Project description:The multivariate nature of cancer necessitates multi-targeted therapy, and kinase inhibitors account for a vast majority of approved cancer therapeutics. While acute promyelocytic leukemia (APL) patients are highly responsive to retinoic acid (RA) therapy, kinase inhibitors have been gaining momentum as co-treatments with RA for non-APL acute myeloid leukemia (AML) differentiation therapies, especially as a means to treat relapsed or refractory AML patients. In this study GW5074 (a c-Raf inhibitor) and PP2 (a Src-family kinase inhibitor) enhanced RA-induced maturation of t(15;17)-negative myeloblastic leukemia cells and rescued response in RA-resistant cells. PD98059 (a MEK inhibitor) and Akti-1/2 (an Akt inhibitor) were less effective, but did tend to promote maturation-uncoupled G1/G0 arrest, while wortmannin (a PI3K inhibitor) did not enhance differentiation surface marker expression or growth arrest. PD98059 and Akti-1/2 did not enhance differentiation markers and have potential, antagonistic off-targets effects on the aryl hydrocarbon receptor (AhR), but neither could the AhR agonist 6-formylindolo(3,2-b)carbazole (FICZ) rescue differentiation events in the RA-resistant cells. GW5074 rescued early CD38 expression in RA-resistant cells exhibiting an early block in differentiation before CD38 expression, while for RA-resistant cells with differentiation blocked later, PP2 rescued the later differentiation marker CD11b; but surprisingly, the combination of the two was not synergistic. Kinases c-Raf, Src-family kinases Lyn and Fgr, and PI3K display highly correlated signaling changes during RA treatment, while activation of traditional downstream targets (Akt, MEK/ERK), and even the surface marker CD38, were poorly correlated with c-Raf or Lyn during differentiation. This suggests that an interrelated kinase module involving c-Raf, PI3K, Lyn and perhaps Fgr functions in a nontraditional way during RA-induced maturation or during rescue of RA induction therapy using inhibitor co-treatment in RA-resistant leukemia cells.

Dataset Information

Src inhibitors, PP2 and dasatinib, increase retinoic acid-induced association of Lyn and c-Raf (S259) and enhance MAPK-dependent differentiation of myeloid leukemia cells.

Publications

Src inhibitors, PP2 and dasatinib, increase retinoic acid-induced association of Lyn and c-Raf (S259) and enhance MAPK-dependent differentiation of myeloid leukemia cells.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets