Targeting ERK1/2 protein-serine/threonine kinases in human cancers

doi:10.1016/j.phrs.2019.01.039

Pharmacological Research

Volume 142, April 2019, Pages 151-168

https://doi.org/10.1016/j.phrs.2019.01.039 Get rights and content

Abstract

ERK1 and ERK2 are key protein kinases that contribute to the Ras-Raf-MEK-ERK MAP kinase signalling module. This pathway participates in the control of numerous processes including apoptosis, cell proliferation, the immune response, nervous system function, and RNA synthesis and processing. MEK1/2 activate human ERK1/2 by first catalyzing the phosphorylation of Y204/187 and then T202/185, both residues of which occur within the activation segment. The phosphorylation of both residues is required for enzyme activation. The only Raf substrates are MEK1/2 and the only MEK1/2 substrates are ERK1/2. In contrast, ERK1/2 catalyze the phosphorylation of many cytoplasmic and nuclear substrates including transcription factors and regulatory molecules. The linear MAP kinase pathway branches extensively at the ERK1/2 node. ERK1/2 are proline-directed kinases that preferentially catalyze the phosphorylation of substrates containing a PxS/TP sequence. The dephosphorylation and inactivation of ERK1/2 is catalyzed by dual specificity phosphatases, protein-tyrosine specific phosphatases, and protein-serine/threonine phosphatases. The combined functions of kinases and phosphatases make the overall process reversible. To provide an idea of the complexities involved in these reactions, somatic cell cycle progression involves the strict timing of more than 32,000 phosphorylation and dephosphorylation events as determined by mass spectrometry. The MAP kinase cascade is perhaps the most important oncogenic driver of human cancers and the blockade of this signalling module by targeted inhibitors is an important anti-tumor strategy. Although numerous cancers are driven by MAP kinase pathway activation, thus far the only orally effective approved drugs that target this signaling module are used for the treatment of BRAF-mutant melanomas. The best treatments include the combination of B-Raf and MEK inhibitors (dabrafenib and trametinib, encorafenib and binimetinib, vemurafenib and cobimetanib). However, resistance to these antagonists occurs within one year and additional treatment options are necessary. Owing to the large variety of malignancies that are driven by dysregulation of the MAP kinase pathway, additional tumor types should be amenable to MAP kinase pathway inhibitor therapy. In addition to new B-Raf and MEK inhibitors, the addition of ERK inhibitors should prove helpful. Ulixertinib, MK-8353, and GDC-0994 are orally effective, potent, and specific inhibitors of ERK1/2 that are in early clinical trials for the treatment of various advanced/metastatic solid tumors. These agents are effective against cell lines that are resistant to B-Raf and MEK1/2 inhibitor therapy. Although MK-8353 does not directly inhibit MEK1/2, it decreases the phosphorylation of ERK1/2 as well as the phosphorylation of RSK, an ERK1/2 substrate. The decrease in RSK phosphorylation appears to be a result of ERK inhibition and the decrease in ERK1/2 phosphorylation is related to the inability of MEK to catalyze the phosphorylation of the ERK–MK-8353 complex; these decreases characterize the ERK dual mechanism inhibition paradigm. Additional work will be required to determine whether ERK inhibitors will be successful in the clinic and are able to forestall the development of drug resistance of the MAP kinase pathway.

Graphical abstract

Section snippets

The Ras-Raf-MEK-ERK (MAP kinase) signaling pathway

Protein kinases play pivotal regulatory roles in nearly every aspect of cell biology [[1], [2], [3]]. They control cell growth, cell proliferation, cell survival, differentiation, the immune response, metabolism, nervous system function, and transcription. Because protein phosphorylation involves the action of both protein kinases as well as phosphoprotein phosphatases, phosphorylation-dephosphorylation is an overall reversible process. To provide an idea of the complexities involved in these

Treatment of human malignancies with Raf and MEK inhibitors

RAS mutations occur in about 33% of all cancers [27,28]. KRAS mutations occur in about 70% of pancreatic ductal adenocarcinomas, 40% of colorectal cancers, 35% of non-small cell lung cancers (NSCLC), 20% of papillary thyroid cancers, 10% of breast and ovarian cancers, and 10% of acute myelogenous and acute lymphoblastic leukemias. Additionally, NRAS mutations occur in about 20% of melanomas and 15% of anaplastic thyroid cancers and follicular thyroid cancers; mutations of HRAS occur in about

Catalytic residues in the amino-terminal and carboxyterminal lobes

Human ERK1 and ERK2, which are 84% identical in their amino acid sequence, share many, if not all, functions [57]. Like nearly all protein kinases, ERK1/2 contain distinctive amino-terminal and carboxyterminal extensions that provide important functional specificity. ERK1 contains an insertion of 17 amino acid residues in its amino-terminal portion. The ERK1/2 family contains an insertion of 32/35 amino acid residues within the protein kinase domain (kinase insert domain) that provides

Classification of protein kinase-drug complexes

Dar and Shokat described three categories of protein kinase inhibitors and classified them as types I, II, and III [103]. Accordingly, type I antagonists bind in the adenine-binding pocket of an active protein kinase; type II antagonists bind to an inactive protein kinase with the activation segment DFG-D pointing away from the active site (DFG-D_out); type III antagonists bind to an allosteric site that is separate from the adenine-binding pocket. Zuccotto later defined type I½ antagonists as

Drug-ligand binding pockets

Liao [121] and van Linden et al. [122] partitioned the region between the protein kinase amino-terminal and carboxyterminal lobes into the front cleft (front pocket), the gate area, and the back cleft. The gate area and back cleft signify the back pocket or hydrophobic pocket II (HPII) (Fig. 4). The front cleft includes the hinge residues, the adenine-binding pocket, the glycine-rich loop and the catalytic loop (HRD(x)₄N) residues. The gate area includes the β3-strand of the N-terminal lobe and

Selected ERK1/2 inhibitors that are in clinical trials

Owing to the frequency of MAP kinase-driven malignancies, it is not surprising that many clinical trials are related to inhibition of this hierarchical three-tiered pathway. More than 300 clinical trials are related to Raf inhibition (clinicaltrials.gov). The relevant diseases include breast, colorectal, renal cell, and other solid tumors, gliomas, melanomas, and NSCLC. KRAS mutant colorectal cancers, esophageal squamous cell carcinomas, and head and neck squamous cell carcinomas have also been

Lipinski’s rule of five

Medicinal chemists and pharmacologists have searched for drug-like chemical properties that result in compounds with oral therapeutic efficacy in a predictable fashion. Lipinski’s rule represents a computational and experimental approach to estimate permeability, solubility, and efficacy in the drug discovery and development setting [138]. In the drug development process the "rule of 5″ predicts that poor permeation or absorption is more likely when there are more than 5 hydrogen-bond donors,

Epilogue and perspective

At the end of 2018, the US FDA had approved 48 small molecule protein kinase inhibitors (see supplementary material), nearly all of which are orally effective with the exception of temsirolimus (which is given intravenously) and netarsudil (which is given as an eye drop). Of the 48 approved small molecule protein kinase inhibitors, the majority (25) inhibit receptor protein-tyrosine kinases, 10 inhibit non-receptor protein-tyrosine kinases, and 13 are directed at protein-serine/threonine

Conflict of interest

The author is unaware of any affiliations, memberships, or financial holdings that might be perceived as affecting the objectivity of this review.

Acknowledgments

The author thanks Laura M. Roskoski for providing editorial and bibliographic assistance. I also thank Josie Rudnicki and Jasper Martinsek help in preparing the figures and Pasha Brezina and W.S. Sheppard for their help in structural analyses. The colored figures in this paper were evaluated to ensure that their perception was accurately conveyed to colorblind readers [168].

References (168)

T. Hunter
Signaling--2000 and beyond
Cell
(2000)
A. Alonso et al.
Protein tyrosine phosphatases in the human genome
Cell
(2004)
A. Plotnikov et al.
The MAPK cascades: signaling components, nuclear roles and mechanisms of nuclear translocation
Biochim. Biophys. Acta
(2011)
R. Roskoski
Targeting oncogenic Raf protein-serine/threonine kinases in human cancers
Pharmacol. Res.
(2018)
A.G. Stephen et al.
Dragging Ras back in the ring
Cancer Cell
(2014)
D.K. Simanshu et al.
RAS proteins and their regulators in human disease
Cell
(2017)
R. Roskoski
RAF protein-serine/threonine kinases: structure and regulation
Biochem. Biophys. Res. Commun.
(2010)
R. Roskoski
MEK1/2 dual-specificity protein kinases: structure and regulation
Biochem. Biophys. Res. Commun.
(2012)
R. Roskoski
Allosteric MEK1/2 inhibitors including cobimetanib and trametinib in the treatment of cutaneous melanomas
Pharmacol. Res.
(2017)
R. Roskoski
ERK1/2 MAP kinases: structure, function, and regulation
Pharmacol. Res.
(2012)

A. Bononi et al.

Protein kinases and phosphatases in the control of cell fate

Enzyme Res.

(2011)

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Invited ReviewTargeting ERK1/2 protein-serine/threonine kinases in human cancers

Abstract

Graphical abstract

Section snippets

The Ras-Raf-MEK-ERK (MAP kinase) signaling pathway

Treatment of human malignancies with Raf and MEK inhibitors

Catalytic residues in the amino-terminal and carboxyterminal lobes

Classification of protein kinase-drug complexes

Drug-ligand binding pockets

Selected ERK1/2 inhibitors that are in clinical trials

Lipinski’s rule of five

Epilogue and perspective

Conflict of interest

Acknowledgments

Cell

Cell

Biochim. Biophys. Acta

Pharmacol. Res.

Cancer Cell

Cell

Biochem. Biophys. Res. Commun.

Biochem. Biophys. Res. Commun.

Pharmacol. Res.

Pharmacol. Res.

Curr. Opin. Cell Biol.

Curr. Opin. Struct. Biol.

Semin. Oncol.

Pharmacol. Res.

Cell

Lancet

Lancet Oncol.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Ther.

Trends Biochem. Sci.

Trends Biochem. Sci.

Ann. Rep. Med. Chem.

Pharmacol. Res.

J. Biol. Chem.

Bioorg. Chem.

Biochim. Biophys. Acta

Cell

J. Biol. Chem.

J. Biol. Chem.

Chem. Biol.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

Pharmacol. Res.

The protein kinase complement of the human genome

Science

SnapShot: phosphoregulation of mitosis

Cell

Protein kinases and phosphatases in the control of cell fate

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Invited Review
Targeting ERK1/2 protein-serine/threonine kinases in human cancers