387 Combination of the ERK inhibitor GDC-0994 with the MEK inhibitor cobimetinib significantly enhances anti-tumor activity in KRAS and BRAF mutant tumor models

Development of small molecule extracellular signal-regulated kinases (ERKs) inhibitors for cancer therapy

The mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway is widely activated by a variety of extracellular stimuli, and its dysregulation is associated with the proliferation, invasion, and migration of cancer cells. ERK1/2 is located at the distal end of this pathway and rarely undergoes mutations, making it an attractive target for anticancer drug development. Currently, an increasing number of ERK1/2 inhibitors have been designed and synthesized for antitumor therapy, among which representative compounds have entered clinical trials. When ERK1/2 signal transduction is eliminated, ERK5 may provide a bypass route to rescue proliferation, and weaken the potency of ERK1/2 inhibitors. Therefore, drug research targeting ERK5 or based on the compensatory mechanism of ERK5 for ERK1/2 opens up a new way for oncotherapy. This review provides an overview of the physiological and biological functions of ERKs, focuses on the structure-activity relationships of small molecule inhibitors targeting ERKs, with a view to providing guidance for future drug design and optimization, and discusses the potential therapeutic strategies to overcome drug resistance.

Elucidation of Abnormal Extracellular Regulated Kinase (ERK) Signaling and Associations with Syndromic and Non-syndromic Autism

Autism is a highly inherited and extremely complex disorder in which results from various cases indicate chromosome anomalies, unusual single-gene mutations, and multiplicative effects of particular gene variants, characterized primarily by impaired speech and social interaction and restricted behavior. The precise etiology of Autism Spectrum Disorder (ASD) is currently unclear. The extracellular signal-regulated kinase (ERK) signaling mechanism affects neurogenesis and neuronal plasticity during the development of the central nervous mechanism. In this regard, the pathway of ERK has recently gained significant interest in the pathogenesis of ASD. The mutation occurs in a few ERK components. Besides, the ERK pathway dysfunction lies in the upstream of modified translation and contributes to synapse pathology in syndromic types of autism. In this review, we highlight the ERK pathway as a target for neurodevelopmental disorder autism. In addition, we summarize the regulation of the ERK pathway with ERK inhibitors in neurological disorders. In conclusion, a better understanding of the ERK signaling pathway provides a range of therapeutic options for autism spectrum disorder.

Two Targets, One Hit: new Anticancer Therapeutics to Prevent Tumorigenesis Without Cardiotoxicity

A serious adverse effect of cancer therapies is cardiovascular toxicity, which significantly limits the widespread use of antineoplastic agents. The promising new field of cardio-oncology offers the identification of potent anti-cancer therapeutics that effectively inhibit cancer cell proliferation without causing cardiotoxicity. Future introduction of recently identified cardio-safe compounds into clinical practice (including ERK dimerization inhibitors or BAX allosteric inhibitors) is expected to help oncologists avoid unwanted cardiological complications associated with therapeutic interventions.

Extracellular Signal-Regulated Kinase (ERK) Inhibitors in Oncology Clinical Trials

The mitogen-activated protein kinase (MAPK) pathway consists of the series of protein kinases RAS-RAF-MEK-Extracellular signal-regulated kinase (ERK), and its function is important to cell proliferation, differentiation, motility, and survival. Certain mutations in the pathway, such as KRAS or BRAF V600 mutations are associated with cancer. Inhibitors of this pathway, including some MEK and BRAF inhibitors, are already being used in the clinic, but a variety of selective ERK inhibitors are still being tested in clinical studies. To date, common adverse events associated with ERK inhibitors include diarrhea, nausea, fatigue, and rash. ERK inhibitors have demonstrated preliminary antitumor activity and may be most effective against cancers with RAS, RAF, or MAPK pathway alterations. This review discusses the MAPK pathway, the biological rationale for ERK inhibitors, and clinical trials involving ERK inhibitors.

Targeting ERK, an Achilles' Heel of the MAPK pathway, in cancer therapy

The mitogen-activated protein kinases (MAPK) pathway, often known as the RAS-RAF-MEK-ERK signal cascade, functions to transmit upstream signals to its downstream effectors to regulate physiological process such as cell proliferation, differentiation, survival and death. As the most frequently mutated signaling pathway in human cancer, targeting the MAPK pathway has long been considered a promising strategy for cancer therapy. Substantial efforts in the past decades have led to the clinical success of BRAF and MEK inhibitors. However, the clinical benefits of these inhibitors are compromised by the frequently occurring acquired resistance due to cancer heterogeneity and genomic instability. This review briefly introduces the key protein kinases involved in this pathway as well as their activation mechanisms. We also generalize the correlations between mutations of MAPK members and human cancers, followed by a summarization of progress made on the development of small molecule MAPK kinases inhibitors. In particular, this review highlights the potential advantages of ERK inhibitors in overcoming resistance to upstream targets and proposes that targeting ERK kinase may hold a promising prospect for cancer therapy.

Cobimetinib: First Global Approval

Genentech (a subsidiary of Roche) and Exelixis are developing cobimetinib, an orally available small molecule, for the treatment of various cancers, including malignant melanoma and breast cancer. Cobimetinib inhibits the MEK (mitogen-activated protein kinase) component of the MAPK/ERK signalling pathway, which is frequently over-activated in human tumours. The product has been approved in Switzerland in combination with vemurafenib for the treatment of patients with unresectable or metastatic BRAF V600 mutation-positive melanoma, and is under regulatory review for the same indication in several countries, including the USA and the EU. This article summarizes the milestones in the development of cobimetinib leading to this first approval for unresectable or metastatic BRAF V600 mutation-positive melanoma melanoma.