SHP1 and SHP2 inhibition enhances the pro-differentiative effect of phorbol esters: an alternative approach against acute myeloid leukemia

Abstract

Background The differentiation-based therapy for acute promyelocytic leukemia (APL) is an inspiring example for the search of novel strategies aimed at treatment of other subtypes of acute myeloid leukemia (AML). Thus, the discovery of new molecular players in cell differentiation becomes a paramount research area to achieve this goal. Here, the involvement of the protein tyrosine phosphatases SHP1 and SHP2 on leukemic cells differentiation is shown, along with the therapeutic possibilities of their targeting to enhance the differentiation induction effect of phorbol esters. Methods The oxidation status and enzymatic activity of SHP1 and SHP2 during PMA-induced differentiation of HEL cells was evaluated. Additionally, the effects of RNAi-mediated downregulation of these phosphatases on cell differentiation was studied. Afterwards, the impact of chemical inhibition of SHP1 and SHP2 on differentiation both in the presence and absence of phorbol esters was tested. Finally, the anti-leukemic potential of phorbol esters and chemical inhibitors of SHP1 and SHP2 was addressed in several AML model cell lines, a xenograft mouse model and AML primary cells in vitro . Results An increase of oxidation with a concomitant decrease of activity was observed for both phosphatases at the onset of PMA-induced differentiation. Consistently, silencing of these proteins favored the process, with an enhanced effect upon their simultaneous downregulation. Moreover, the proteins SRC and β-catenin were identified as downstream targets of SHP1 and SHP2 in this context. In agreement with these findings, chemical inhibition of the phosphatases promoted cell differentiation itself and enhanced the effect of phorbol esters. Interestingly, treatment with the phorbol ester prostratin and the dual inhibitor of SHP1 and SHP2 NSC87877 synergistically hampered the proliferation of AML cell lines, prolonged the survival of xenografted mice and reduced the clonogenic potential of AML primary cells. Conclusions SHP1 and SHP2 are relevant mediators of differentiation in AML cells and their inhibition either alone or in combination with prostratin seems a promising differentiation-based therapeutic strategy against different subtypes of AML beyond APL. Electronic supplementary material The online version of this article (10.1186/s13046-019-1097-z) contains supplementary material, which is available to authorized users.

Nucleoredoxin Downregulation Reduces β-Catenin Levels and Shifts Hematopoietic Differentiation towards Myeloid Lineage In Vitro

“…In addition, the transient oxidation and inactivation of the SRC homology domain containing protein tyrosine phosphatases 1 (SHP1) and 2 (SHP2) is required to trigger the same differentiation processes. Interestingly, downregulation of these proteins results in a decrease in β-catenin levels [9]. This work supports the influence of redox signaling on the Wnt/β-catenin pathway and encourages the study of redox-sensitive proteins that may link these two cellular processes.…”

“…PTPs are probably the best studied representatives of the second group, with reversible oxidation of their active center as an important mechanism to modulate their catalytic activity [7]. Indeed, they have a direct role in hematopoietic differentiation [8,9]. On the other hand, thioredoxin family proteins have been mainly studied in the context of redox homeostasis rather than cellular signaling.…”

Ajuforrestin A, an Abietane Diterpenoid from Ajuga ovalifolia var. calanthe, Induces A549 Cell Apoptosis by Targeting SHP2

“…Our study revealed that compound 2 directly targeted SHP2 and restrained A549 cell proliferation in a concentration-dependent manner. The research also found that inhibition or deletion of SHP2 resulted in myeloma and leukemia cell apoptosis [ 29 , 30 ]. We found that incubation with compound 2 caused a significant increase in early and late apoptotic A549 cells, and the apoptosis-related pathways were also activated.…”

Biology, pathology, and therapeutic targeting of RAS

“…NSC87877) that bound the catalytic cleft of both SHP1 and SHP2, inhibited their activity, and attenuated activation of RAS and MAPK (Chen et al, 2006). NSC87877 reduced proliferation of leukemia cell lines and enhanced survival of mice with HL-60 xenografts when co-treated with a PKC activator, indicating that oncogenic RAS is susceptible to SHP2 inhibition in vivo (Perez-Fernandez et al, 2019). II-B08 bound the catalytic domain of SHP2 and inhibited EGF-stimulated MAPK activation in HEK293 and NIH 3T3 cells (Zhang et al, 2010).…”

“…Data were compiled from the Catalogue of Somatic Mutations (COSMIC), v86 (Forbes et al, 2017). (James, et al, 1993;Kohl, et al, 1994;Reiss, et al, 1990) Natural (Gibbs, et al, 1993;Hara, et al, 1993 (Desjardins, et al, 2011;Eskens, et al, 2001;Gordon, et al, 2018;Kieran, et al, 2007;Kim, et al, 2005;Njoroge, et al, 1998;Ravoet, et al, 2008; Currently: NCT02383927, NCT03496766 (Alsina, et al, 2004;Burnett, et al, 2012;Crul, et al, 2002;Rao, et al, 2004 (Hahn, et al, 2002;Lobell, et al, 2002;Morgan, et al, 2012) Bisphospohates Mouse leukemia model Perez-Fernandez, et al, 2019;Tsutsumi, et al, 2018) II-B08 IC 50 = 5.5μM SHP2 inhibitor Catalytic domain ↑pY32 / ↓effector binding Cell culture; Mouse glioma model (Bunda, et al, 2015;Tsutsumi, et al, 2018;Zhang, et al, 2010) 11a-1 IC 50 = 200nM SHP2 inhibitor Catalytic domain ↑pY32 / ↓effector binding 2/3D cell culture (Kano, et al, 2019;Tsutsumi, et al, 2018;Zeng, et al, 2014a) PHPS1 IC 50 = 2.1μM; K i = 0.73μM SHP2 inhibitor Catalytic domain ↑pY32 / ↓effector binding Ex vivo 3Dtransdifferentiation assay (Hellmuth, et al, 2008;…”