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Background: The main drawback of BRAF/MEK inhibitors (BRAF/MEKi)-based targeted therapy in the management of BRAF-mutated cutaneous metastatic melanoma (MM) is the development of therapeutic resistance. We aimed to assess in this context the role of mTORC2, a signaling complex defined by the presence of the essential RICTOR subunit, regarded as an oncogenic driver in several tumor types, including MM., Methods: After analyzing The Cancer Genome Atlas MM patients' database to explore both overall survival and molecular signatures as a function of intra-tumor RICTOR levels, we investigated the effects of RICTOR downregulation in BRAF V600E MM cell lines on their response to BRAF/MEKi. We performed proteomic screening to identify proteins modulated by changes in RICTOR expression, and Seahorse analysis to evaluate the effects of RICTOR depletion on mitochondrial respiration. The combination of BRAFi with drugs targeting proteins and processes emerged in the proteomic screening was carried out on RICTOR-deficient cells in vitro and in a xenograft setting in vivo., Results: Low RICTOR levels in BRAF-mutated MM correlate with a worse clinical outcome. Gene Set Enrichment Analysis of low-RICTOR tumors display gene signatures suggestive of activation of the mitochondrial Electron Transport Chain (ETC) energy production. RICTOR-deficient BRAF V600E cells are intrinsically tolerant to BRAF/MEKi and anticipate the onset of resistance to BRAFi upon prolonged drug exposure. Moreover, in drug-naïve cells we observed a decline in RICTOR expression shortly after BRAFi exposure. In RICTOR-depleted cells, both mitochondrial respiration and expression of nicotinamide phosphoribosyltransferase (NAMPT) are enhanced, and their pharmacological inhibition restores sensitivity to BRAFi., Conclusions: Our work unveils an unforeseen tumor-suppressing role for mTORC2 in the early adaptation phase of BRAF V600E melanoma cells to targeted therapy and identifies the NAMPT-ETC axis as a potential therapeutic vulnerability of low RICTOR tumors. Importantly, our findings indicate that the evaluation of intra-tumor RICTOR levels has a prognostic value in metastatic melanoma and may help to guide therapeutic strategies in a personalized manner., (© 2024. The Author(s).)

MEK inhibitors (MEKi) represent innovative and promising treatments for managing manifestations of neurofibromatosis type 1 (NF1). To mitigate potential ophthalmic side effects, such as MEKi-associated retinopathy (MEKAR), patients undergoing MEKi therapy routinely receive ophthalmology evaluations. Our study aims to assess the necessity of this regular screening within a predominantly pediatric NF1 population by examining the occurrence of ocular adverse events (OAE). A retrospective study evaluated 45 NF1 patients receiving MEKi. Inclusion criteria included baseline and follow-up examinations following the initiation of MEKi therapy. At each assessment, a comprehensive eye evaluation was performed, comprising a dilated fundus examination, ocular coherence tomography of the macula and nerve fiber layer, and Humphrey visual field testing. Twenty-six patients, with an average age of 13 years (range 2-23 years) and an average follow-up duration of 413 days were included in the analysis. Three different MEKi were used: selumetinib (77%), trametinib (23%), and mirdametinib (4%). None of the patients experienced retinopathy at any point during the study. Some patients had pre-existing optic neuropathies (27%), but no instances of nerve changes occurred after commencing MEKi therapy. Four patients (15%) exhibited symptoms of dry eye, all of which were effectively managed with topical lubrication.

Recent findings have highlighted the essential role of dual leucine zipper kinase (DLK) in neuronal degeneration. Saraswatharishta (SWRT), an ayurvedic formulation utilized in traditional Indian medicine, has demonstrated effectiveness in addressing neurodegenerative diseases. Herein, we aim to delve into the atomistic details of the mode of action of phytochemicals present in SWRT against DLK. Our screening process encompassed over 500 distinct phytochemicals derived from the main ingredients of the SWRT formulation. Through a comparative analysis of docking scores and relative poses, we successfully identified four novel compounds, which underwent further investigation via 2 × 500 ns long molecular dynamics (MD) simulations. Among the top four compounds, CID16066851 sourced from the Acorus calamus displayed the most stable complex with DLK. The molecular mechanics Poisson - Boltzmann surface area (MM-PBSA) calculations highlighted the significance of electrostatic and van der Waals interactions in the binding recognition process. Additionally, we identified key residues, namely Phe192, Leu243, Val139, and Leu141, as hotspots that predominantly govern the DLK-inhibitor interaction. Notably, the leading compounds are sourced from the Acorus calamus, Syzygium aromaticum, Zingiber officinale, and Anethum sowa plants present in the SWRT formulation. Overall, the findings of our study hold promise for future drug development endeavors combating neurodegenerative conditions.Communicated by Ramaswamy H. Sarma.

Tumor necrosis factor α (TNF-α) has been demonstrated to be a therapeutic target for autoimmune diseases. However, this biological therapy exhibits some inevitable disadvantages, such as risk of infection. Thus, small-molecule alternatives by targeting TNF-α production signaling pathway are still in demand. Herein, we describe the design, synthesis, and structure-activity relationships of 3-aryindanone compounds regarding their modulation of TNF-α production. Among them, ( R )-STU104 exhibited the most potent inhibitory activity on TNF-α production, which suppressed the TAK1/MKK3/p38/MnK1/MK2/elF4E signal pathways through binding with MKK3 and disrupting the TAK1 phosphorylating MKK3. As a result, ( R )-STU104 demonstrated remarkable dose-effect relationships on both acute and chronic mouse UC models. In addition to its good pharmacokinetic (PK) and safety profile, ( R )-STU104 showed better anti-UC efficacy in vivo at 10 mg/kg/d than mesalazine at the dose of 50 mg/kg/d. These results suggested that TAK1-MKK3 interaction inhibitors could be potentially utilized for the treatment of UC.

The ongoing COVID-19 pandemic is one of the biggest health challenges of recent decades. Among the causes of mortality triggered by SARS-CoV-2 infection, the development of an inflammatory "cytokine storm" (CS) plays a determinant role. Here, we used transcriptomic data from the bronchoalveolar lavage fluid (BALF) of COVID-19 patients undergoing a CS to obtain gene-signatures associated to this pathology. Using these signatures, we interrogated the Connectivity Map (CMap) dataset that contains the effects of over 5000 small molecules on the transcriptome of human cell lines, and looked for molecules which effects on transcription mimic or oppose those of the CS. As expected, molecules that potentiate immune responses such as PKC activators are predicted to worsen the CS. In addition, we identified the negative regulation of female hormones among pathways potentially aggravating the CS, which helps to understand the gender-related differences in COVID-19 mortality. Regarding drugs potentially counteracting the CS, we identified glucocorticoids as a top hit, which validates our approach as this is the primary treatment for this pathology. Interestingly, our analysis also reveals a potential effect of MEK inhibitors in reverting the COVID-19 CS, which is supported by in vitro data that confirms the anti-inflammatory properties of these compounds., (© 2022. The Author(s).)

Objective: Dual leucine zipper kinase (DLK), which regulates the c-Jun N-terminal kinase pathway involved in axon degeneration and apoptosis following neuronal injury, is a potential therapeutic target in amyotrophic lateral sclerosis (ALS). This first-in-human study investigated safety, tolerability, and pharmacokinetics (PK) of oral GDC-0134, a small-molecule DLK inhibitor. Plasma neurofilament light chain (NFL) levels were explored in GDC-0134-treated ALS patients and DLK conditional knockout (cKO) mice., Methods: The study included placebo-controlled, single and multiple ascending-dose (SAD; MAD) stages, and an open-label safety expansion (OLE) with adaptive dosing for up to 48 weeks., Results: Forty-nine patients were enrolled. GDC-0134 (up to 1200 mg daily) was well tolerated in the SAD and MAD stages, with no serious adverse events (SAEs). In the OLE, three study drug-related SAEs occurred: thrombocytopenia, dysesthesia (both Grade 3), and optic ischemic neuropathy (Grade 4); Grade ≤2 sensory neurological AEs led to dose reductions/discontinuations. GDC-0134 exposure was dose-proportional (median half-life = 84 h). Patients showed GDC-0134 exposure-dependent plasma NFL elevations; DLK cKO mice also exhibited plasma NFL compared to wild-type littermates., Interpretation: This trial characterized GDC-0134 safety and PK, but no adequately tolerated dose was identified. NFL elevations in GDC-0134-treated patients and DLK cKO mice raised questions about interpretation of biomarkers affected by both disease and on-target drug effects. The safety profile of GDC-0134 was considered unacceptable and led to discontinuation of further drug development for ALS. Further work is necessary to understand relationships between neuroprotective and potentially therapeutic effects of DLK knockout/inhibition and NFL changes in patients with ALS., (© 2022 Genentech, Inc. Annals of Clinical and Translational Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)

The RAF1 :p.Ser257Leu variant is associated with severe Noonan syndrome (NS), progressive hypertrophic cardiomyopathy (HCM), and pulmonary hypertension. Trametinib, a MEK-inhibitor approved for treatment of RAS/MAPK-mutated cancers, is an emerging treatment option for HCM in NS. We report a patient with NS and HCM, treated with Trametinib and documented by global RNA sequencing before and during treatment to define transcriptional effects of MEK-inhibition. A preterm infant with HCM carrying the RAF1 :p.Ser257Leu variant, rapidly developed severe congestive heart failure (CHF) unresponsive to standard treatments. Trametinib was introduced (0.022 mg/kg/day) with prompt clinical improvement and subsequent amelioration of HCM at ultrasound. The appearance of pulmonary artery aneurysm and pulmonary hypertension contributed to a rapid worsening after ventriculoperitoneal shunt device placement for posthemorrhagic hydrocephalus: she deceased for untreatable CHF at 3 months of age. Autopsy showed severe obstructive HCM, pulmonary artery dilation, disarrayed pulmonary vascular anatomy consistent with pulmonary capillary hemangiomatosis. Transcriptome across treatment, highlighted robust transcriptional changes induced by MEK-inhibition. Our findings highlight a previously unappreciated connection between pulmonary vascular disease and the severe outcome already reported in patients with RAF1 -associated NS. While MEK-inhibition appears a promising therapeutic option for HCM in RASopathies, it appears insufficient to revert pulmonary hypertension.

Background: Non-small cell lung cancer (NSCLC) is the leading cause of cancer death worldwide. Chemotherapy, the treatment of choice in non-operable cases, achieves a dismal success rate, raising the need for new therapeutic options. In about 25% of NSCLC, the activating mutations of the KRAS oncogene define a subclass that cannot benefit from tyrosine kinase inhibitors (TKIs). The tumor suppressor miR-16 is downregulated in many human cancers, including NSCLC. The main objectives of this study were to evaluate miR-16 treatment to restore the TKI sensitivity and compare its efficacy to MEK inhibitors in KRAS -mutated NSCLC., Methods: We performed in vitro and in vivo studies to investigate whether miR-16 could be exploited to overcome TKI resistance in KRAS-mutated NSCLC. We had three goals: first, to identify the KRAS downstream effectors targeted by mir-16, second, to study the effects of miR-16 restoration on TKI resistance in KRAS-mutated NSCLC both in vitro and in vivo, and finally, to compare miR-16 and the MEK inhibitor selumetinib in reducing KRAS-mutated NSCLC growth in vitro and in vivo., Results: We demonstrated that miR-16 directly targets the three KRAS downstream effectors MAPK3 , MAP2K1 , and CRAF in NSCLC, restoring the sensitivity to erlotinib in KRAS -mutated NSCLC both in vitro and in vivo. We also provided evidence that the miR-16-erlotinib regimen is more effective than the selumetinib-erlotinib combination in KRAS -mutated NSCLC., Conclusions: Our findings support the biological preclinical rationale for using miR-16 in combination with erlotinib in the treatment of NSCLC with KRAS -activating mutations.

Background: Melanoma brain metastases (MBM) have a poor prognosis. Systemic treatments that have improved outcomes in advanced melanoma have been shown to have an intracranial (IC) effect. We studied the efficacy and outcomes of combined immune checkpoint inhibitor ipilimumab/nivolumab (Combi-ICI) or targeted therapy (Combi-TT) as first-line treatment in MBM., Methods: MBM patients treated with Combi-ICI or Combi-TT within 3 months after MBM diagnosis. Endpoints were progression-free survival (PFS) and overall survival (OS)., Results: 53 patients received Combi-ICI, 32% had symptomatic MBM and 33.9% elevated LDH. 71.7% required local treatment. The disease control rate was 60.3%. IC response rate (RR) was 43.8% at 3-months with durable responses at 6- (46.5%) and 12-months (53.1%). Extracranial (EC) RR was 44.7% at 3-months and 50% at 12-months. Median PFS was 9.6 months (95% CI 3.6-NR) and median overall survival (mOS) 44.8 months (95% CI; 26.2-NR). 63 patients received Combi-TT, 55.6% of patients had symptomatic MBM, 57.2% of patients had elevated LDH and 68.3% of patients required local treatment. The disease control rate was 60.4%. ICRR was 50% at 3-months, but dropped at 6-months (20.9%). ECRR was 69.2% at 3-months and 17.6% at 12-months. Median PFS was 5.8 months (95% CI 4.2-7.6) and mOS 14.2 months (95% CI 8.99-26.8). In BRAFV600 patients, 26.7% of patients received Combi-ICI and 73.3% Combi-TT with OS (p = 0.0053) and mPFS (p = 0.03) in favour to Combi-ICI., Conclusion: Combi-ICI showed prolonged mOS with sustainable IC and EC responses. Despite the initially increased efficacy, Combi-TT responses at 12 months were low. Combi-ICI appeared superior to Combi-TT for OS and PFS in BRAFV600 patients. Other clinical factors are determinants for first-line treatment choice., Competing Interests: Conflict of interest statement RD has intermittent, project focused consulting and/or advisory relationships with Novartis, Merck Sharp & Dhome (MSD), Bristol-Myers Squibb (BMS), Roche, Amgen, Takeda, Pierre Fabre outside the submitted work. JM has intermittent project focused consultant or advisory relationships with Merck/Pfizer, Merck Sharp & Dohme, Amgen, Novartis and Pierre Fabre and has received travel support from Ultrasun, L’ oreal, Merck Sharp & Dohme, Bristol Myers and Squibb und Pierre Fabre outside of the submitted work. PL has received honoraria from Bristol-Myers Squibb (BMS) and Pfizer. PB receives travel support from MSD and honoraria from Novartis. GAM has been a consultant or advisor for Provectus; received research funding from Pfizer, Celgene, and Ventana; and has had travel accommodation and expenses paid for by Roche and Novartis. OM reports grants and personal fees from Bristol Myers Squibb (BMS), grants and personal fees from MSD, personal fees from Roche, outside the submitted work. LZ reports honoraria from Roche, BMS, MSD, Novartis, Pierre Fabre; Consultant or Advisory Role: BMS, Novartis, Pierre Fabre, Sunpharma, Sanofi, MSD; Research funding to institution: Novartis; Travel support: BMS, Pierre Fabre, Sanofi, Amgen, Novartis, Sunpharma. MPL receives project specific research funding, unrelated to the work presented here, from Roche, Novartis, Molecular Partners, and Oncobit AG. FD, CLG, MLH, KK and PC have declared no conflicts of interest., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The advent of mitogen-activated protein kinase (MAPK) inhibitors that directly inhibit tumor growth and of immune checkpoint inhibitors (ICI) that boost effector T cell responses have strongly improved the treatment of metastatic melanoma. In about half of all melanoma patients, tumor growth is driven by gain-of-function mutations of BRAF (v-rat fibrosarcoma (Raf) murine sarcoma viral oncogene homolog B), which results in constitutive ERK activation. Patients with a BRAF mutation are regularly treated with a combination of BRAF and MEK (MAPK/ERK kinase) inhibitors. Next to the antiproliferative effects of BRAF/MEKi, accumulating preclinical evidence suggests that BRAF/MEKi exert immunomodulatory functions such as paradoxical ERK activation as well as additional effects in non-tumor cells. In this review, we present the current knowledge on the immunomodulatory functions of BRAF/MEKi as well as the non-intended effects of ICI and discuss the potential synergistic effects of ICI and MAPK inhibitors in melanoma treatment.

The RAF/MEK/ERK pathway is central to the control of cell physiology, and its dysregulation is associated with many cancers. Accordingly, the proteins constituting this pathway, including MEK1/2 (MEK), have been subject to intense drug discovery and development efforts. Allosteric MEK inhibitors (MEKi) exert complex effects on RAF/MEK/ERK pathway signaling and are employed clinically in combination with BRAF inhibitors in malignant melanoma. Although mechanisms and structures of MEKi bound to MEK have been described for many of these compounds, recent studies suggest that RAF/MEK complexes, rather than free MEK, should be evaluated as the target of MEKi. Here, we describe structural and biochemical studies of eight structurally diverse, clinical-stage MEKi to better understand their mechanism of action on BRAF/MEK complexes. We find that all of these agents bind in the MEK allosteric site in BRAF/MEK complexes, in which they stabilize the MEK activation loop in a conformation that is resistant to BRAF-mediated dual phosphorylation required for full activation of MEK. We also show that allosteric MEK inhibitors act most potently on BRAF/MEK complexes rather than on free active MEK, further supporting the notion that a BRAF/MEK complex is the physiologically relevant pharmacologic target for this class of compounds. Our findings provide a conceptual and structural framework for rational development of RAF-selective MEK inhibitors as an avenue to more effective and better-tolerated agents targeting this pathway., Competing Interests: Competing interest statement: M.J.E. has received sponsored research support from Novartis Institutes for Biomedical Research and Takeda Pharmaceuticals. M.J.E. is a consultant for Novartis Institutes for Biomedical Research and H3 Biomedicines.

Objective: To assess whether RAF and MEK inhibitors (RAFi/MEKi) can provide long-term clinical benefit in adult patients with BRAF V600-mutant glial and glioneuronal tumors (GGNTs), we analyzed tumor response and long-term outcome in a retrospective cohort., Methods: We performed a retrospective search in the institutional databases of 6 neuro-oncology departments for adult patients with recurrent or disseminated BRAF V600-mutant GGNTs treated with RAFi/MEKi., Results: Twenty-eight adults with recurrent or disseminated BRAF V600-mutant gangliogliomas (n = 9), pleomorphic xanthoastrocytomas (n = 9), and diffuse gliomas (n = 10) were included in the study. At the time that treatment with RAFi/MEKi was started, all tumors displayed radiologic features of high-grade neoplasms. Thirteen patients received RAFi as single agents (vemurafenib [n = 11], dabrafenib [n = 2]), and 15 received combinations of RAFi/MEKi (vemurafenib + cobimetinib [n = 5], dabrafenib + trametinib [n = 10]). Eleven patients achieved a partial or complete response (11 of 28, 39%), with a median reduction of -78% in their tumor burden. Responders experienced a median increase of 10 points in their Karnofsky Performance Status (KPS) score and a median progression-free survival of 18 months, which was longer than achieved with first-line treatment (i.e., 7 months, p = 0.047). Responders had better KPS score ( p = 0.018) and tended to be younger ( p = 0.061) and to be treated earlier ( p = 0.099) compared to nonresponders. Five patients were rechallenged with RAFi/MEKi at progression, with novel tumor responses in 2. On univariate and multivariate analyses, response to RAFi/MEKi was an independent predictor of overall survival., Conclusions: Our study highlights the long-term clinical benefits of RAFi/MEKi in adult patients with BRAF V600-mutant GGNTs and encourages rechallenge in responders., Classification of Evidence: This study provides Class III evidence that, for adult patients with BRAF V600-mutant GGNT, RAFi/MEKi can reduce tumor burden and provide clinical benefit., (© 2021 American Academy of Neurology.)

Background: RAS variant-related functional impact on the mitogen-activated protein kinase (MAPK) pathway, and correlation between MAPK activation and MAPK/ERK kinase (MEK) inhibitor responsiveness, is not established., Patients and Methods: Of 1,693 tumours sequenced, 576 harboured a RAS alteration; 62 patients received an MEK inhibitor (MEKi) and had RAS mutations that were functionally characterised. We report that RAS mutants have variable levels of MAPK activity, as measured by a functional cell-based assay that quantified MAPK pathway activation after transfection with a variety of RAS mutations., Results: Patients with tumours harbouring RAS alterations with high versus low MAPK activity who were treated with an MEKi showed significantly longer median progression-free survival (PFS) (5.0 vs. 2.3 months; p = 0.0034) and overall survival (20.0 vs. 5.0 months; p = 0.0146) and a trend towards higher rates of clinical benefit (stable disease ≥6 months or partial/complete remission) (38% versus 15%; p = 0.095) (p-values as per univariate analysis). PFS remained statistically significant after the multivariate analysis (p = 0.003)., Conclusions: These results support a correlation between RAS-mutant cancers with greater MAPK signalling and PFS after MEKi treatment., Competing Interests: Conflict of interest statement S.K. serves as a consultant for Foundation Medicine and receives speaker fees from Roche. R.P. is an employee of Turning Point Therapeutics, Inc. O.Z., G.T. and M.V. are full-time employees of NovellusDx. R.K. receives research funding from Genentech, Merck, Serono, Pfizer, Sequenom, Foundation Medicine, Konica Minolta, Grifols and Guardant; reports consultant fees from XBiotech, Loxo, Neomed, Actuate Therapeutics, Pfizer and Merck; reports speaker fees from Roche; has an ownership interest in IDbyDNA and CureMatch Inc. and serves on the board of CureMatch and CureMetrix Inc. R.O. does not have a conflict of interest. S.L. does not have a conflict of interest., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

TAK1 is a serine/threonine kinase which is involved in the moderation of cell survival and death via the TNFα signalling pathway. It is also implicated in a range of cancer and anti-inflammatory diseases. Drug discovery efforts on this target have focused on both traditional reversible ATP-binding site inhibitors and increasingly popular irreversible covalent binding inhibitors. Irreversible inhibitors can offer benefits in terms of potency, selectivity and PK/PD meaning they are increasingly pursued where the strategy exists. TAK1 kinase differs from the better-known kinase EGFR in that the reactive cysteine nucleophile targeted by electrophilic inhibitors is located towards the back of the ATP binding site, not at its mouth. While a wealth of structural and computational effort has been spent exploring EGFR, only limited studies on TAK1 have been reported. In this work we report the first QM/MM study on TAK1 aiming to better understand aspects of covalent adduct formation. Our goal is to identify the general base in the catalytic reaction, whether the process proceeds via a stepwise or concerted pathway, and how the highly flexible G-loop and A-loop affect the catalytic cysteine located nearby.

Background: Treatment with immune checkpoint and BRAF/MEK inhibitors has significantly improved the survival of patients with advanced cutaneous melanoma and other metastatic malignancies. Therapy-related uveitis is a rare ocular adverse event, which may potentially lead to legal blindness. The epidemiology of treatment-related uveitis is currently insufficiently known., Patients and Methods: In this cohort study, we asked whether exposure to either immune checkpoint or BRAF/MEK inhibitors was associated with a higher risk of developing uveitis compared with the general population. Based on a Bayesian framework, we estimated the probability of developing uveitis with a right-censored, exponential survival model using data from the Zurich Melanoma Registry. The registry included all adult patients treated for advanced cutaneous melanoma between January 2008 and December 2018 at the University Hospital of Zurich, Switzerland., Results: In total, 304 patients (64%) were treated with immune checkpoint and 186 patients (38%) with BRAF/MEK inhibitors. Median follow-up time was 74 days (interquartile range: 57-233 days). Eleven patients developed uveitis and 30 patients died. We estimated the probability of developing uveitis per year in the general population as 0.05% (95% credibility interval [CrI]: 0.02%-0.1%). Corresponding posterior probabilities of treatment-related uveitis were 3.48% (95% CrI: 0.93%-7.49%) and 5.04% (95% CrI: 2.07%-9.19%) for immune checkpoint or BRAF/MEK inhibitors (posterior probability for difference: 76%)., Conclusions: Immune checkpoint and particularly BRAF/MEK inhibitor therapies are associated with an increase in the risk of developing uveitis. Treatment-related uveitis is not associated with systemic adverse events of immune checkpoint or BRAF/MEK inhibitors., Competing Interests: Conflict of interest statement FD receives intermittent travel support from Amgen and Pierre Fabre outside of the submitted work. JM has intermittent project focused consultant or advisory relationships with Merck/Pfizer, Merck Sharp & Dohme and Pierre Fabre and has received travel support from Ultrasun, L’Oréal, Merck Sharp & Dohme, Bristol-Myers Squibb (BMS) and Pierre Fabre outside of the submitted work. RD has intermittent, project focused consulting and/or advisory relationships with Novartis, Merck Sharp & Dohme (MSD), Bristol-Myers Squibb (BMS), Roche, Amgen, Takeda, Pierre Fabre, Sun Pharma, Sanofi outside the submitted work. MU is supported by a Vanier Canada Graduate Scholarship from the Canadian Institutes of Health Research. CE, NM and UU declared no conflicts of interest., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objective: Diabetic retinopathy, one of retinal vasculopathy, is characterized by retinal inflammation, vascular leakage, blood-retinal barrier breakdown, and neovascularization. However, the molecular mechanisms that contribute to diabetic retinopathy progression remain unclear. Approach and Results: Tpl2 (tumor progression locus 2) is a protein kinase implicated in inflammation and pathological vascular angiogenesis. N ε -carboxymethyllysine (CML) and inflammatory cytokines levels in human sera and in several diabetic murine models were detected by ELISA, whereas liquid chromatography-tandem mass spectrometry analysis was used for whole eye tissues. The CML and p-Tpl2 expressions on the human retinal pigment epithelium (RPE) cells were determined by immunofluorescence. Intravitreal injection of pharmacological inhibitor or NA (neutralizing antibody) was used in a diabetic rat model. Retinal leukostasis, optical coherence tomography, and H&E staining were used to observe pathological features. Sera of diabetic retinopathy patients had significantly increased CML levels that positively correlated with diabetic retinopathy severity and foveal thickness. CML and p-Tpl2 expressions also significantly increased in the RPE of both T1DM and T2DM diabetes animal models. Mechanistic studies on RPE revealed that CML-induced Tpl2 activation and NADPH oxidase, and inflammasome complex activation were all effectively attenuated by Tpl2 inhibition. Tpl2 inhibition by NA also effectively reduced inflammatory/angiogenic factors, retinal leukostasis in streptozotocin-induced diabetic rats, and RPE secretion of inflammatory cytokines. The attenuated release of angiogenic factors led to inhibited vascular abnormalities in the diabetic animal model., Conclusions: The inhibition of Tpl2 can block the inflammasome signaling pathway in RPE and has potential clinical and therapeutic implications in diabetes-associated retinal microvascular dysfunction.

The importance of transforming growth factor beta-activated kinase 1 (TAK1) to cell survival has been demonstrated in many studies. TAK1 regulates signalling cascades, the NF-κB pathway and the mitogen-activated protein kinase (MAPK) pathway. TAK1 inhibitors can induce the apoptosis of cancerous cells, and irreversible inhibitors such as (5Z)-7-oxozeaenol are highly potent. However, they can react non-specifically with cysteine residues in proteins, which may have serious adverse effects. Reversible covalent inhibitors have been suggested as alternatives. We synthesised imidazopyridine derivatives as novel TAK1 inhibitors, which have 2-cyanoacrylamide moiety that can form reversible covalent bonding. A derivative with 2-cyano-3-(6-methylpyridin-2-yl)acrylamide ( 13h ) exhibited potent TAK1 inhibitory activity with an IC 50 of 27 nM. It showed a reversible reaction with β-mercaptoethanol, which supports its potential as a reversible covalent inhibitor.

Introduction: Anti-PD-1 monotherapies (aPD-1) and BRAF/MEK inhibitors (BRAF/MEKi) changed the BRAF-mutant advanced melanoma treatment landscape. This study aimed to improve the understanding of real-world treatment patterns and optimal treatment sequence., Methods: This was a retrospective study of BRAF-mutant advanced melanoma patients who initiated 1L aPD-1 or BRAF/MEKi in the US Oncology Network between 1 January 2014 and 31 December 2017, followed through 31 December 2018. Patient and treatment characteristics were assessed descriptively, with Kaplan-Meier methods used for time-to-event endpoints. As the primary analysis, overall survival (OS) and physician-assessed progression-free survival (rwPFS) were evaluated with Cox proportional hazard regression models and propensity score matching (n = 49)., Results: A total of 224 patients were included (median age 61 years, 62.9% male, 89.7% white): 36.2% received aPD-1 and 63.8% BRAF/MEKi. Median OS and rwPFS were longer among aPD-1 vs BRAF/MEKi patients (OS: not reached vs 13.9 months, log-rank P = .0169; rwPFS: 7.6 vs 6.5 months, log-rank P = .0144). Receipt of aPD-1 was associated with improved OS (HR = 0.602 vs BRAF/MEKi [95%CI 0.382-0.949]; P = .0287). Among patients without an event within 6 months of 1L initiation, receipt of aPD-1 was associated with a decreased risk of progression or death from 6 months onwards (HR = 0.228 [95%CI 0.106-0.493]; P = .0002). This association was not observed among patients within 6 months of 1L initiation (HR = 1.146; 95% CI 0.755-1.738). Results from the propensity score-matched pairs were consistent with these trends., Conclusion: These results suggest a clinical benefit of 1L aPD-1 compared to BRAF/MEKi after 6 months of treatment for BRAF-mutant advanced melanoma. Future research should explore factors associated with early progression and their relationship with clinical outcomes., (© 2020 Merck Sharp & Dohme. Cancer Medicine published by John Wiley & Sons Ltd.)

Preclinical modeling suggests that intermittent BRAF inhibitor therapy may delay acquired resistance when blocking oncogenic BRAF V600 in melanoma 1,2 . We conducted S1320, a randomized, open-label, phase 2 clinical trial (NCT02196181) evaluating whether intermittent dosing of the BRAF inhibitor dabrafenib and the MEK inhibitor trametinib improves progression-free survival in patients with metastatic and unresectable BRAF V600 melanoma. Patients were enrolled at 68 academic and community sites nationally. All patients received continuous dabrafenib and trametinib during an 8-week lead-in period, after which patients with non-progressing tumors were randomized to either continuous or intermittent dosing of both drugs on a 3-week-off, 5-week-on schedule. The trial has completed accrual and 206 patients with similar baseline characteristics were randomized 1:1 to the two study arms (105 to continuous dosing, 101 to intermittent dosing). Continuous dosing yielded a statistically significant improvement in post-randomization progression-free survival compared with intermittent dosing (median 9.0 months versus 5.5 months, P = 0.064, pre-specified two-sided α = 0.2). Therefore, contrary to the initial hypothesis, intermittent dosing did not improve progression-free survival in patients. There were no differences in the secondary outcomes, including overall survival and the overall incidence of treatment-associated toxicity, between the two groups.

Over the years, tumor progression locus 2 (TPL2) has been identified as an essential modulator of immune responses that conveys inflammatory signals to downstream effectors, subsequently modulating the generation and function of inflammatory cells. TPL2 is also differentially expressed and activated in several cancers, where it is associated with increased inflammation, malignant transformation, angiogenesis, metastasis, poor prognosis and therapy resistance. However, the relationship between TPL2-driven inflammation, tumorigenesis and tumor immunity has not been addressed. Here, we reconcile the function of TPL2-driven inflammation to oncogenic functions such as inflammation, proliferation, apoptosis resistance, angiogenesis, metastasis, immunosuppression and immune evasion. We also address the controversies reported on TPL2 function in tumor-promoting inflammation and tumorigenesis, and highlight the potential role of the TPL2 adaptor function in regulating the mechanisms leading to pro-tumorigenic inflammation and tumor progression. We discuss the therapeutic implications and limitations of targeting TPL2 for cancer treatment. The ideas presented here provide some new insight into cancer pathophysiology that might contribute to the development of more integrative and specific anti-inflammatory and anti-cancer therapeutics., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Introduction: BRAF is a confirmed therapeutic target in non-small cell lung cancer (NSCLC), as the BRAF inhibitor dabrafenib, in combination with the MEK inhibitor trametinib, is approved for the treatment of NSCLC harbouring BRAF V600E mutation. Scant evidence is available concerning the mechanisms of resistance to BRAF/MEK inhibitors in BRAF V600E NSCLC., Patients and Methods: Patients with BRAF V600E NSCLC with acquired resistance to BRAF/MEK inhibitors were included in the institutional, prospective MATCH-R (from "Matching Resistance") trial and underwent tumour and liquid biopsies at the moment of radiological progression. Extensive molecular analyses were performed, including targeted next-generation sequencing (NGS), whole-exome sequencing (WES), RNA sequencing and comparative genomic hybridisation (CGH) array., Results: Of the 11 patients included, eight had progressed on dabrafenib-trametinib combination, two on dabrafenib monotherapy and one on vemurafenib (BRAF inhibitor). Complete molecular analyses were available for seven patients, whereas an additional case had only targeted NGS and CGH array data. Among these eight patients, acquired molecular events potentially responsible for resistance were detected in three who progressed on dabrafenib-trametinib combination, that is, MEK1 K57N, RAS viral (v-ras) oncogene homolog (NRAS) Q61R and rat sarcoma viral oncogene homolog (KRAS) Q61R mutations. One patient progressing on dabrafenib monotherapy developed a PTEN frameshift mutation. No molecular hints addressing resistance emerged in the remaining four patients with analyses performed. Tumour mutational burden, evaluated by WES in seven patients, was low (median = 2.06 mutations/megabase, range = 1.57-3.75 mut/Mb)., Conclusions: Novel resistance mechanisms to BRAF/MEK inhibitors in BRAF V600E NSCLC were identified, pointing out the recurring involvement of the MAPK pathway and guiding the development of new treatment strategies., Competing Interests: Conflict of interest statement F.F. reports attending editorial activities sponsored by Roche and BMS. L.M. reports serving a consulting and advisory role for Roche Diagnostics, reports participating in lectures and educational activities for Bristol-Myers Squibb, Tecnofarma, Roche and AstraZeneca and reports receiving funds for travel, accommodations and expenses from Chugai. A.G. reports receiving funds for travel, accommodation, congress registration expenses from Boehringer Ingelheim, Novartis, Pfizer and Roche. A.G. reports serving a consultant/expert role for Novartis and serving as a Principal/sub-Investigator of Clinical Trials for Aduro Biotech, Agios Pharmaceuticals, Amgen, Argen-X Bvba, Arno Therapeutics, Astex Pharmaceuticals, Astra Zeneca, Aveo, Bayer Healthcare Ag, Bbb Technologies Bv, Beigene, Bioalliance Pharma, Biontech Ag, Blueprint Medicines, Boehringer Ingelheim, Bristol Myers Squibb, Ca, Celgene Corporation, Chugai Pharmaceutical Co., Clovis Oncology, Daiichi Sankyo, Debiopharm S.A., Eisai, Exelixis, Forma, Gamamabs, Genentech, Inc., Gilead Sciences, Inc, Glaxosmithkline, Glenmark Pharmaceuticals, H3 Biomedicine, Inc, Hoffmann La Roche Ag, Incyte Corporation, Innate Pharma, Iris Servier, Janssen, Kura Oncology, Kyowa Kirin Pharm, Lilly, Loxo Oncology, Lytix Biopharma As, Medimmune, Menarini Ricerche, Merck Sharp & Dohme Chibret, Merrimack Pharmaceuticals, Merus, Millennium Pharmaceuticals, Nanobiotix, Nektar Therapeutics, Novartis Pharma, Octimet Oncology Nv, Oncoethix, Oncomed, Oncopeptides, Onyx Therapeutics, Orion Pharma, Oryzon Genomics, Pfizer, Pharma Mar, Pierre Fabre, Rigontec Gmbh, Roche, Sanofi Aventis, Sierra Oncology, Taiho Pharma, Tesaro, Inc, Tioma Therapeutics, Inc. and Xencor. A.G. reports receiving research grants from Astrazeneca, BMS, Boehringer Ingelheim, Janssen Cilag, Merck, Novartis, Pfizer, Roche and Sanofi and non-financial support (drug supplied) from Astrazeneca, Bayer, BMS, Boringher Ingelheim, Johnson & Johnson, Lilly, Medimmune, Merck, NH TherAGuiX, Pfizer and Roche. J.A. reports serving as advisor/consultant roles for AstraZeneca, Bayer, BMS, MSD and Roche and reports receiving research funding form MSD. C.M. reports receiving consultant/advisory fees from Amgen, Astellas, Astra Zeneca, Bayer, BeiGene, BMS, Celgene, Debiopharm, Genentech, Ipsen, Janssen, Lilly, MedImmune, MSD, Novartis, Pfizer, Roche, Sanofi and Orion and reports serving as a Principal/sub-Investigator of Clinical Trials for Abbvie, Aduro, Agios, Amgen, Argen-x, Astex, AstraZeneca, Aveopharmaceuticals, Bayer, Beigene, Blueprint, BMS, BoeringerIngelheim, Celgene, Chugai, Clovis, Daiichi Sankyo, Debiopharm, Eisai, Eos, Exelixis, Forma, Gamamabs, Genentech, Gortec, GSK, H3 biomedecine, Incyte, InnatePharma, Janssen, Kura Oncology, Kyowa, Lilly, Loxo, Lysarc, Lytix Biopharma, Medimmune, Menarini, Merus, MSD, Nanobiotix, Nektar Therapeutics, Novartis, Octimet, Oncoethix, Oncopeptides AB, Orion, Pfizer, Pharmamar, Pierre Fabre, Roche, Sanofi, Servier, Sierra Oncology, Taiho, Takeda, Tesaro and Xencor. F.A. reports receiving grants from Novartis, AstraZeneca, Pfizer, Lilly, Roche and Daiichi Sankyo. K.H. reports being an employee and shareholder of Inivata. B.B. reports receiving sponsor for research at Gustave Roussy Cancer Centre, Abbvie, Amgen, AstraZeneca, BeiGene, Blueprint Medicines, BMS, Boehringer Ingelheim, Celgene, Cristal Therapeutics, Daiichi-Sankyo, Eli Lilly, GSK, Ignyta, IPSEN, Inivata, Janssen, Merck KGaA, MSD, Nektar, Onxeo, OSE immunotherapeutics, Pfizer, Pharma Mar, Roche-Genentech, Sanofi, Servier, Spectrum Pharmaceuticals, Takeda, Tiziana Pharma and Tolero Pharmaceuticals. J.-C.S. reports receiving consultancy fees from AstraZeneca, Astex, Clovis, GSK, GamaMabs, Lilly, MSD, Mission Therapeutics, Merus, Pfizer, PharmaMar, Pierre Fabre, Roche/Genentech, Sanofi, Servier, Symphogen and Takeda over the last 5 years. J.-C.S. reports being a full-time employee of AstraZeneca until December 2019. J.-C.S. reports being a shareholder of AstraZeneca and Gritstone. D.P. reports serving consulting, advisory role or lectures for AstraZeneca, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Daiichi Sankyo, Eli Lilly, Merck, Novartis, Pfizer, prIME Oncology, Peer CME and Roche; reports receiving honoraria from AstraZeneca, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Merck, Novartis, Pfizer, prIME Oncology, Peer CME and Roche; reports conducting clinical trials research for AstraZeneca, Bristol-Myers Squibb, Boehringer Ingelheim, Eli Lilly, Merck, Novartis, Pfizer, Roche, Medimmun, Sanofi-Aventis, Taiho Pharma, Novocure and Daiichi Sankyo and reports receiving funding for travel, accommodations and expenses from AstraZeneca, Roche, Novartis, prIME Oncology and Pfizer. All other authors have no conflicts of interest to disclose., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Sepsis is a main reason for death in intensive care units, inflammation is closely related to sepsis. Anti-inflammation plays an important role in treating of sepsis. ZT01 is a triptolide derivative with strong anti-inflammatory activity and low toxicity. The purpose of this study is to evaluate the anti-inflammatory activity of ZT01 under the sepsis condition and explore the underlying molecular mechanisms. Two in vivo model of sepsis, caecal ligation and puncture or intraperitoneal injection of LPS in C57BL/6, were used to evaluate the therapeutic effects of ZT01. In vitro, the anti-inflammatory properties of ZT01 were assessed in IFN-γ or LPS-induced macrophages by ELISA, RT-PCR, western blotting and co-immunoprecipitation. Macrophages were used to investigate the polarization phenotype by flow cytometry. The results showed, ZT01 significantly attenuated inflammatory response of sepsis in serum or lung tissue by inhibiting production of pro-inflammatory factors and improved the survival rate of septic mice in vivo. In cultured macrophages, ZT01 not only decreased the levels of TNF-α and IL-6 but also prevented the TKA1-TAB1 complex formation, thereby inhibiting the phosphorylation expression of MKK4 and JNK, which were all stimulated by LPS. Moreover, ZT01 inhibited the LPS-induced polarization of macrophages into pro-inflammatory phenotype. Adoptive transfer ZT01 pretreated bone marrow-derived macrophages obviously reduced the pro-inflammatory factors in mice after LPS challenge. Our findings suggested that ZT01 exhibited anti-inflammation activity via preventing the pro-inflammatory phenotype of macrophages by blocking the formation of the TAK1-TAB1 complex and subsequently phosphorylation of MKK4 and JNK., Competing Interests: Declaration of Competing Interest The authors declare no conflicts of interest., (Copyright © 2020 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Treatment paradigms for advanced melanoma have changed fundamentally over recent years. A discrete choice experiment was performed to explore patient preferences regarding outcome (overall response rate, 2-year survival rate, progression-free survival, time to response, type of adverse events, probability of adverse event-related treatment discontinuation) and process attributes (frequency and route of administration, frequency of consultations) of modern treatments for melanoma. Mean preferences of 150 patients with melanoma stage IIC-IV were highest for overall response rate (relative importance score (RIS) 26.8) and 2-year survival (RIS 21.6), followed by type of adverse events (RIS 11.7) and probability of adverse event-related treatment discontinuation (RIS 9.2). Interest in overall response rate and 2-year survival declined with increasing age, whereas process attributes gained importance. Participants who had experienced treatment with immune checkpoint inhibitors valued overall response rate more highly and worried less about the type of adverse events. In conclusion, patients with advanced melanoma consider efficacy of treatment options most important, followed by safety, but preferences vary with individual and disease-related characteristics.

ZAK is a new promising target for discovery of drugs with activity against antihypertrophic cardiomyopathy (HCM). A series of 1,2,3-triazole benzenesulfonamides were designed and synthesized as selective ZAK inhibitors. One of these compounds, 6p binds tightly to ZAK protein ( K d = 8.0 nM) and potently suppresses the kinase function of ZAK with single-digit nM (IC 50 = 4.0 nM) and exhibits excellent selectivity in a KINOMEscan screening platform against a panel of 403 wild-type kinases. This compound dose dependently blocks p38/GATA-4 and JNK/c-Jun signaling and demonstrates promising in vivo anti-HCM efficacy upon oral administration in a spontaneous hypertensive rat (SHR) model. Compound 6p may serve as a lead compound for new anti-HCM drug discovery.

Dysregulation of intracellular signaling pathways is a key attribute of diseases associated with chronic inflammation, including cancer. Mitogen activated protein kinases have emerged as critical conduits of intracellular signal transmission, yet due to their ubiquitous roles in cellular processes, their direct inhibition may lead to undesired effects, thus limiting their usefulness as therapeutic targets. Mixed lineage kinases (MLKs) are mitogen-activated protein kinase kinase kinases (MAP3Ks) that interact with scaffolding proteins and function upstream of p38, JNK, ERK, and NF-kappaB to mediate diverse cellular signals. Studies involving gene silencing, genetically engineered mouse models, and small molecule inhibitors suggest that MLKs are critical in tumor progression as well as in inflammatory processes. Recent advances indicate that they may be useful targets in some types of cancer and in diseases driven by chronic inflammation including neurodegenerative diseases and metabolic diseases such as nonalcoholic steatohepatitis. This review describes existing MLK inhibitors, the roles of MLKs in various aspects of tumor progression and in the control of inflammatory processes, and the potential for therapeutic targeting of MLKs., Competing Interests: Declaration of Competing Interest None, (Copyright © 2019. Published by Elsevier Inc.)

Purpose of Review: Better understanding of the biology of BRAF-mutated melanoma has led to the development of highly effective therapy, BRAF and MEK inhibitors, targeting abnormally activated protein kinases for patient with BRAF-mutated melanoma. The purpose of this article was to review the recent published data on BRAF and MEK inhibitors in melanoma in the metastatic, adjuvant and neoadjuvant setting to facilitate the management of melanoma patients in clinical practice., Recent Findings: The spectacular outcomes of targeted therapy in advanced melanoma patients have led to their development in the adjuvant setting with substantial improvements in recurrence-free and overall survival. The neoadjuvant strategy is already used in many cancers to decrease tumor load, improve resectability and prevent relapse. Targeted therapy in the neoadjuvant setting is a therapeutic approach being explored in subsequent studies., Summary: We hope that this review will help clinicians to manage melanoma patients in routine practice.

Interleukin-1 receptor-associated kinase-1 (IRAK-1) and IRAK-4, as well as transforming growth factor β-activated kinase 1 (TAK1), are protein kinases essential for transducing inflammatory signals from interleukin receptors. IRAK family proteins and TAK1 have high sequence identity within the ATP-binding pocket, limiting the development of highly selective IRAK-1/4 or TAK1 inhibitors. Beyond kinase activity, IRAKs and TAK1 act as molecular scaffolds along with other signaling proteins, complicating the interpretation of experiments involving knockin or knockout approaches. In contrast, pharmacological manipulation offers the promise of targeting catalysis-mediated signaling without grossly disrupting the cellular architecture. Recently, we reported the discovery of takinib, a potent and highly selective TAK1 inhibitor that has only marginal activity against IRAK-4. On the basis of the TAK1-takinib complex structure and the structure of IRAK-1/4, here we defined critical contact sites of the takinib scaffold within the nucleotide-binding sites of each respective kinase. Kinase activity testing of takinib analogs against IRAK-4 identified a highly potent IRAK-4 inhibitor (HS-243). In a kinome-wide screen of 468 protein kinases, HS-243 had exquisite selectivity toward both IRAK-1 (IC 50 = 24 nm) and IRAK-4 (IC 50 = 20 nm), with only minimal TAK1-inhibiting activity (IC 50 = 0.5 μm). Using HS-243 and takinib, we evaluated the consequences of cytokine/chemokine responses after selective inhibition of IRAK-1/4 or TAK1 in response to lipopolysaccharide challenge in human rheumatoid arthritis fibroblast-like synoviocytes. Our results indicate that HS-243 specifically inhibits intracellular IRAKs without TAK1 inhibition and that these kinases have distinct, nonredundant signaling roles., (© 2020 Scarneo et al.)

Background: Sixty percent of patients with stage IV melanoma may develop brain metastases, which result in significantly increased morbidity and a poor overall prognosis. Phase 3 studies of melanoma usually exclude patients with untreated brain metastases; therefore, clinical data for intracranial responses to treatments are limited., Methods: A multicenter, retrospective case series investigation of consecutive BRAF-mutant patients with melanoma brain metastases (MBMs) treated with a combination of BRAF inhibitor encorafenib and MEK inhibitor binimetinib was conducted to evaluate the antitumor response. Assessments included the intracranial, extracranial, and global objective response rates (according to the modified Response Evaluation Criteria in Solid Tumors, version 1.1); the clinical benefit rate; the time to response; the duration of response; and safety., Results: A total of 24 patients with stage IV BRAF-mutant MBMs treated with encorafenib plus binimetinib in 3 centers in the United States were included. Patients had received a median of 2.5 prior lines of treatment, and 88% had prior treatment with BRAF/MEK inhibitors. The intracranial objective response rate was 33%, and the clinical benefit rate was 63%. The median time to a response was 6 weeks, and the median duration of response was 22 weeks. Among the 21 patients with MBMs and prior BRAF/MEK inhibitor treatment, the intracranial objective response rate was 24%, and the clinical benefit rate was 57%. Similar outcomes were observed for extracranial and global responses. The safety profile for encorafenib plus binimetinib was similar to that observed in patients with melanoma without brain metastases., Conclusions: Combination therapy with encorafenib plus binimetinib elicited intracranial activity in patients with BRAF-mutant MBMs, including patients previously treated with BRAF/MEK inhibitors. Further prospective studies are warranted and ongoing., (© 2019 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.)

Cancer persister cells tolerate anticancer drugs and serve as the founders of acquired resistance and cancer relapse. Here we show that a subpopulation of BRAF V600 mutant melanoma cells that tolerates exposure to BRAF and MEK inhibitors undergoes a reversible remodelling of mRNA translation that evolves in parallel with drug sensitivity. Although this process is associated with a global reduction in protein synthesis, a subset of mRNAs undergoes an increased efficiency in translation. Inhibiting the eIF4A RNA helicase, a component of the eIF4F translation initiation complex, abrogates this selectively increased translation and is lethal to persister cells. Translation remodelling in persister cells coincides with an increased N6-methyladenosine modification in the 5'-untranslated region of some highly translated mRNAs. Combination of eIF4A inhibitor with BRAF and MEK inhibitors effectively inhibits the emergence of persister cells and may represent a new therapeutic strategy to prevent acquired drug resistance.

Background: Although BRAF/MEK inhibitors are generally considered to be equally effective whether given before or after immunotherapy, no prospective trial has confirmed this hypothesis and contradictory data have been published in the melanoma field., Objective: We aimed to investigate the outcomes of patients with metastatic melanoma depending on the first-line treatment., Patients and Methods: In this ambidirectional cohort, single-center study, we included 253 consecutive melanoma patients treated in our institution with an anti-PD1 antibody or BRAF/MEK inhibitors, who started first-line treatment between December 2015 and March 2018. Kaplan-Meier estimator, log-rank test, and Cox proportional hazard model were used in this analysis., Results: First-line median progression-free survival (PFS) for all patients was 5.7 months (m), 6.9 m on anti-PD-1 therapy and 5.6 m for combination targeted therapy. Patients with BRAF mutated melanoma had 6.0 m median PFS on immunotherapy. At a median follow-up of 23.2 m with 149 events, in BRAF wild-type patients treated with anti-PD1, median overall survival (OS) was 18.1 m. BRAF mutated patients treated with first-line BRAF/MEK inhibitors had 11.7 m median OS. High neutrophil to lymphocyte ratio, high LDH level, ECOG > 0, and the presence of brain metastases negatively impacted PFS and OS., Conclusions: In BRAF mutated patients with normal LDH, first-line immunotherapy seems a more effective approach. We have demonstrated that although BRAF mutation is a negative prognostic factor in stage IV melanoma, the use of two different systemic treatment modalities allows achievement of comparable survival in BRAF mutated and BRAF wild-type patients.

Background: Clinical response to MAPK inhibitors in metastatic melanoma patients is heterogeneous for reasons still needing to be elucidated. As the patient immune activity contributes to treatment clinical benefit, the pre-existing level of immunity at tumor site may provide biomarkers of disease outcome to therapy. Here we investigated whether assessing the density and spatial tissue distribution of key immune cells in the tumor microenvironment could identify patients predisposed to respond to MAPK inhibitors., Methods: Pretreatment tumor biopsies from a total of 213 patients (158 for the training set and 55 for the validation set) treated with BRAF or BRAF/MEK inhibitors within the Italian Melanoma Intergroup were stained with selected immune markers (CD8, CD163, β-catenin, PD-L1, PD-L2). Results, obtained by blinded immunohistochemical scoring and digital image analysis, were correlated with clinical response and outcome by multivariate logistic models on response to treatment and clinical outcome, adjusted for American Joint Committee on Cancer stage, performance status, lactate dehydrogenase and treatment received., Results: Patients with high intratumoral, but not peritumoral, CD8 + T cells and concomitantly low CD163 + myeloid cells displayed higher probability of response (OR 9.91, 95% CI 2.23-44.0, p = 0.003) and longer overall survival (HR 0.34, 95% CI 0.16-0.72, p = 0.005) compared to those with intratumoral low CD8 + T cells and high CD163 + myeloid cells. The latter phenotype was instead associated with a shorter progression free survival (p = 0.010). In contrast, PD-L1 and PD-L2 did not correlate with clinical outcome while tumor β-catenin overexpression showed association with lower probability of response (OR 0.48, 95% CI 0.21-1.06, p = 0.068)., Conclusions: Analysis of the spatially constrained distribution of CD8 + and CD163 + cells, representative of the opposite circuits of antitumor vs protumor immunity, respectively, may assist in identifying melanoma patients with improved response and better outcome upon treatment with MAPK inhibitors. These data underline the role of endogenous immune microenvironment in predisposing metastatic melanoma patients to benefit from therapies targeting driver-oncogenic pathways.

Background: Protoporphyrin IX (PpIX) gets accumulated preferentially in 5-aminolevulinic acid (5-ALA)-treated cancer cells. Photodynamic therapy (PDT) utilises the accumulated PpIX to trigger cell death by light-induced generation of reactive oxygen species (ROS). We previously demonstrated that oncogenic Ras/MEK decreases PpIX accumulation in cancer cells. Here, we investigated whether combined therapy with a MEK inhibitor would improve 5-ALA-PDT efficacy., Methods: Cancer cells and mice models of cancer were treated with 5-ALA-PDT, MEK inhibitor or both MEK inhibitor and 5-ALA-PDT, and treatment efficacies were evaluated., Results: Ras/MEK negatively regulates the cellular sensitivity to 5-ALA-PDT as cancer cells pre-treated with a MEK inhibitor were killed more efficiently by 5-ALA-PDT. MEK inhibition promoted 5-ALA-PDT-induced ROS generation and programmed cell death. Furthermore, the combination of 5-ALA-PDT and a systemic MEK inhibitor significantly suppressed tumour growth compared with either monotherapy in mouse models of cancer. Remarkably, 44% of mice bearing human colon tumours showed a complete response with the combined treatment., Conclusion: We demonstrate a novel strategy to promote 5-ALA-PDT efficacy by targeting a cell signalling pathway regulating its sensitivity. This preclinical study provides a strong basis for utilising MEK inhibitors, which are approved for treating cancers, to enhance 5-ALA-PDT efficacy in the clinic.

We report in this work the discovery of novel allosteric MEK inhibitors by pharmacophore modeling and virtual screening. Two out of 13 virtual hit compounds were identified as MEK kinase inhibitors using a MEK1 binding assay. Structural derivations on the hit compound M100 (IC 50  = 27.2 ± 4.5 μM in RAF-MEK cascading assay) by substituent transformation and bioisosterism replacement have led to the synthesis of a small library of carbazoles. The enzymatic studies revealed the preliminary structure-activity relationships and the derivative 22k (IC 50  = 12.8 ± 0.5 μM) showed the most potent inhibitory effect against Raf-MEK cascading. Compound 7 was discovered as toxic as M100 to tumor cells whereas safer to HEK293 cells (IC 50  > 100 μM) than M100 (IC 50  = 8.9 ± 2.0 μM). It suggests that carbazole is a good scaffold for the design of novel MEK inhibitors for therapeutic uses. More importantly, the developed pharmacophore model can serve as a reliable criterion in novel MEK inhibitor discovery., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Background: Melanoma is a potentially fatal malignancy with poor prognosis. Several recent studies have demonstrated that combination therapy of BRAF and MEK inhibition achieved better curative effect and appeared less toxic effects. We conducted a meta-analysis to evaluate the efficacy and safety between BRAF inhibition plus MEK inhibition combination therapy and BRAF inhibition monotherapy in melanoma patients., Methods: We performed the search in PubMed, EMBASE, and the Cochrane Library from January 2010 to January 2019. Inclusion and exclusion of studies, assessment of quality, outcome measures, data extraction, and synthesis were independently accomplished by two reviewers. Revman 5.3 software was used for the meta-analysis., Results: Totally, seven randomized controlled trials involving 3146 patients met our inclusion criteria. Comparing the results of combination therapy and monotherapy, combination therapy significantly improved OS (RR = 1.13; 95% CI, 1.08, 1.19; P < 0.00001), ORR (RR = 1.36; 95% CI, 1.28, 1.45; P < 0.00001), PFS (RR = 0.57; 95% CI, 0.52, 0.63; P < 0.00001) and reduced deaths (RR = 0.78; 95% CI, 0.69, 0.88; P < 0.0001). Skin-related adverse events such as hyperkeratosis, cutaneous squamous-cell carcinoma were less compared with monotherapy. However, gastrointestinal events like nausea, diarrhea, and vomiting were at a higher frequency., Conclusion: Doublet BRAF and MEK inhibition achieved better survival outcomes over single-agent BRAF inhibition and occurred less skin-related events, but gastrointestinal events were more in combination therapy., (© 2019 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Background: Patients who have unresectable or metastatic melanoma with a BRAF V600E or V600K mutation have prolonged progression-free survival and overall survival when receiving treatment with BRAF inhibitors plus MEK inhibitors. However, long-term clinical outcomes in these patients remain undefined. To determine 5-year survival rates and clinical characteristics of the patients with durable benefit, we sought to review long-term data from randomized trials of combination therapy with BRAF and MEK inhibitors., Methods: We analyzed pooled extended-survival data from two trials involving previously untreated patients who had received BRAF inhibitor dabrafenib (at a dose of 150 mg twice daily) plus MEK inhibitor trametinib (2 mg once daily) in the COMBI-d and COMBI-v trials. The median duration of follow-up was 22 months (range, 0 to 76). The primary end points in the COMBI-d and COMBI-v trials were progression-free survival and overall survival, respectively., Results: A total of 563 patients were randomly assigned to receive dabrafenib plus trametinib (211 in the COMBI-d trial and 352 in the COMBI-v trial). The progression-free survival rates were 21% (95% confidence interval [CI], 17 to 24) at 4 years and 19% (95% CI, 15 to 22) at 5 years. The overall survival rates were 37% (95% CI, 33 to 42) at 4 years and 34% (95% CI, 30 to 38) at 5 years. In multivariate analysis, several baseline factors (e.g., performance status, age, sex, number of organ sites with metastasis, and lactate dehydrogenase level) were significantly associated with both progression-free survival and overall survival. A complete response occurred in 109 patients (19%) and was associated with an improved long-term outcome, with an overall survival rate of 71% (95% CI, 62 to 79) at 5 years., Conclusions: First-line treatment with dabrafenib plus trametinib led to long-term benefit in approximately one third of the patients who had unresectable or metastatic melanoma with a BRAF V600E or V600K mutation. (Funded by GlaxoSmithKline and Novartis; COMBI-d ClinicalTrials.gov number, NCT01584648; COMBI-v ClinicalTrials.gov number, NCT01597908.)., (Copyright © 2019 Massachusetts Medical Society.)

This retrospective cohort study assessed the prognostic significance of distant metastasis-free interval (DMFI) in patients with relapsed BRAF-mutant melanoma treated with BRAF with or without MEK inhibitors (BRAFi ± MEKi). Patients with a DMFI of up to 24 months were compared with those with DMFI of more than 24 months, with regard to their postrelapse progression-free survival (PR-PFS) and overall survival (PR-OS). In total, 109 patients were included in the study. Median DMFI was 25.3 (range: 3.4-188.2) months. Median PR-PFS in patients with DMFI of more than 24 months was 7.9 months [95% confidence interval (CI): 6.2-9.7] compared with 5.4 (95% CI: 4.2-6.7) months of those with shorter DMFI (P = 0.016). Median PR-OS was 15.6 months (95% CI: 13.6-17.6) in patients with DMFI of more than 24 months and 12.0 months (95% CI: 9.0-15.0) with DMFI of up to 24 months (P = 0.289). Multivariate Cox regression analysis showed that DMFI was independently and strongly associated with improved PR-PFS (adjusted hazard ratio = 3.21, 95% CI: 1.78-5.77, ≤ 24 vs. > 24 months) and longer PR-OS (adjusted hazard ratio: 2.09, 95% CI: 1.15-3.80, ≤ 24 vs. > 24 months). The present cohort study is one of the first to confirm the association of DMFI of more than 24 months with an indolent disease course, as shown by longer PR-PFS and PR-OS, in patients with relapsed stage IV melanoma treated by BRAF inhibitor/MEK inhibitor.

Purpose: Immune checkpoint inhibitors (ICI) and BRAF and MEK inhibitors (BMi) have improved survival in metastatic melanoma (MM). However, the experience of long-term responders remains undescribed. This study characterised survivorship issues faced by long-term responders to ICI or BMi., Methods: Patients with MM, aged ≥ 18 years old, ≥ 6 months post-ICI or BMi initiation with an objective response or stable disease. A 72-question survey assessed physical and psychological effects, impact on lifestyle, access to information, satisfaction with care, and availability of supports., Results: One hundred and five of 120 (88%) patients completed the survey (ICI 69/BMI 36). For the ICI cohort, 39 (57%) were receiving ongoing treatment, 17 ceased due to toxicity and 13 due to a sustained response. For the BMi cohort, 31 (85%) were receiving ongoing treatment, 4 ceased due to toxicity and 1 due to a sustained complete response. At data cut-off on 18 December 2018, median PFS (range) was 2.5 years (1.3-8.5) for ICI and 3.1 years (0.6-7.3) for BMi. Long-term toxicities included dry/itchy skin (ICI 51, 74%/ BMi 25, 69%), arthralgias (ICI 30, 58%/ BMi 23, 64%) and fatigue (ICI 62, 90%/ BMi 33, 92%). Psychological morbidity was common, including anxiety awaiting results (ICI 50, 72%/ BMi 29, 81%), fear of melanoma recurring or progressing (ICI 56, 81%/ BMi 31, 86%) or death (ICI 44, 64%/ BMi 26, 72%)., Conclusion: MM survivors experience chronic treatment toxicities and frequently report psychological concerns., Implications for Cancer Survivors: Survivors may benefit from discussions regarding long-term toxicities and tailored psychological supports.

Epithelioid glioblastoma is a rare aggressive variant of glioblastoma (GBM) characterized by a dismal prognosis of about 6 months and frequent leptomeningeal dissemination. A recent study has revealed that 50% of epithelioid GBMs harbor three genetic alterations - BRAF V600E mutation, TERT promoter mutations, and homozygous deletions of CDKN2A/2B. Emerging evidence support the effectiveness of targeted therapies for brain tumors with BRAF V600E mutation. Here we describe a dramatic radiographical response to combined therapy with BRAF and MEK inhibitors in a patient with epithelioid GBM harboring BRAF V600E mutation, characterized by thick spinal dissemination. From relapsed tumor procured at autopsy, we established a cell line retaining the BRAF V600E mutation, TERT promoter mutation and CDKN2A/2B loss. Intracranial implantation of these cells into mice resulted in tumors closely resembling the original, characterized by epithelioid tumor cells and dissemination, and invasion into the perivascular spaces. We then confirmed the efficacy of treatment with BRAF and MEK inhibitor both in vitro and in vivo. Epithelioid GBM with BRAF V600E mutation can be considered a good treatment indication for precision medicine, and this patient-derived cell line should be useful for prediction of the tumor response and clarification of its biological characteristics.

Philadelphia chromosome-like (Ph-like) acute lymphoblastic leukemia (ALL) is a genetically heterogeneous subtype of B-cell ALL characterized by chromosomal rearrangements and mutations that result in aberrant cytokine receptor and kinase signaling. In particular, chromosomal rearrangements resulting in the overexpression of cytokine receptor-like factor 2 (CRLF2) occur in 50% of Ph-like ALL cases. CRLF2 overexpression is associated with particularly poor clinical outcomes, though the molecular basis for this is currently unknown. Glucocorticoids (GCs) are integral to the treatment of ALL and GC resistance at diagnosis is an important negative prognostic factor. Given the importance of GCs in ALL therapy and the poor outcomes for patients with CRLF2 overexpression, we hypothesized that the aberrant signal transduction associated with CRLF2 overexpression might mediate intrinsic GC insensitivity. To test this hypothesis, we exposed Ph-like ALL cells from patient-derived xenografts to GCs and found that CRLF2 rearranged (CRLF2R) leukemias uniformly demonstrated reduced GC sensitivity in vitro. Furthermore, targeted inhibition of signal transduction with the MEK inhibitor trametinib and the Akt inhibitor MK2206, but not the JAK inhibitor ruxolitinib, was sufficient to augment GC sensitivity. These data suggest that suboptimal GC responses may in part underlie the poor clinical outcomes for patients with CRLF2 overexpression and provide rationale for combination therapy involving GCs and signal transduction inhibitors as a means of enhancing GC efficacy., Competing Interests: The authors have declared that no competing interests exist.

Therapeutic developments for neurodegenerative disorders are redirecting their focus to the mechanisms that contribute to neuronal connectivity and the loss thereof. Using a high-throughput microscopy pipeline that integrates morphological and functional measurements, we found that inhibition of dual leucine zipper kinase (DLK) increased neuronal connectivity in primary cortical cultures. This neuroprotective effect was not only observed in basal conditions but also in cultures depleted from antioxidants and in cultures in which microtubule stability was genetically perturbed. Based on the morphofunctional connectivity signature, we further showed that the effects were limited to a specific dose and time range. Thus, our results illustrate that profiling microscopy images with deep coverage enables sensitive interrogation of neuronal connectivity and allows exposing a pharmacological window for targeted treatments. In doing so, we revealed a broad-spectrum neuroprotective effect of DLK inhibition, which may have relevance to pathological conditions that ar.e associated with compromised neuronal connectivity.

Background: Targeting the epidermal growth factor receptor (EGFR) either alone or in combination with chemotherapy is an effective treatment for patients with RAS wild-type metastatic colorectal cancer (mCRC). However, only a small percentage of mCRC patients receive clinical benefits from anti-EGFR therapies, due to the development of resistance mechanisms. In this regard, HER2 has emerged as an actionable target in the treatment of mCRC patients with resistance to anti-EGFR therapy., Methods: We have used SW48 and LIM1215 human colon cancer cell lines, quadruple wild-type for KRAS, NRAS, BRAF and PI3KCA genes, and their HER2-amplified (LIM1215-HER2 and SW48-HER2) derived cells to perform in vitro and in vivo studies in order to identify novel therapeutic strategies in HER2 gene amplified human colorectal cancer., Results: LIM1215-HER2 and SW48-HER2 cells showed over-expression and activation of the HER family receptors and concomitant intracellular downstream signaling including the pro-survival PI3KCA/AKT and the mitogenic RAS/RAF/MEK/MAPK pathways. HER2-amplified cells were treated with several agents including anti-EGFR antibodies (cetuximab, SYM004 and MM151); anti-HER2 (trastuzumab, pertuzumab and lapatinib) inhibitors; anti-HER3 (duligotuzumab) inhibitors; and MEK and PI3KCA inhibitors, such as refametinib and pictilisib, as single agents and in combination. Subsequently, different in vivo experiments have been performed. MEK plus PI3KCA inhibitors treatment determined the best antitumor activity. These results were validated in vivo in HER2-amplified patient derived tumor xenografts from three metastatic colorectal cancer patients., Conclusions: These results suggest that combined therapy with MEK and PI3KCA inhibitors could represent a novel and effective treatment option for HER2-amplified colorectal cancer.

The clinical significance of BRAF alterations in well-differentiated (WD) metastatic pancreatic neuroendocrine tumor (panNET) is unknown, but BRAF-mutated panNET could represent a subset characterized by an identifiable and clinically actionable driver. Following the identification of two patients with WD metastatic panNET whose tumors harbored BRAF mutations, we queried the MSK-IMPACT series of 80 patients with WD metastatic panNET for additional mutations in BRAF, and in other genes involved in RAS/ RTK/ PI3K signaling pathways. BRAF mutations were identified in six samples (7.5%): two tumors harbored V600E mutations, one tumor each expressed K601E, T599K, and T310I mutations, and one tumor expressed both G596D and E451K BRAF. Few additional actionable driver alterations were identified. To determine the ERK activating capability of four BRAF mutations not previously characterized, mutant constructs were tested in model systems. Biochemical characterization of BRAF mutations revealed both high and low activity mutants. Engineered cells expressing BRAF K601E and V600E were used for in vitro drug testing of RAF and MEK inhibitors currently in clinical use. BRAF K601E demonstrated reduced sensitivity to dabrafenib compared to BRAF V600E, but the combination of RAF plus MEK inhibition was effective in cells expressing this mutation. Herein, we describe the clinical course of a patient with BRAF K601E and a patient with BRAF V600E WD metastatic panNET, and the identification of four mutations in BRAF not previously characterized. The combined clinical and biochemical data support a potential role for RAF and MEK inhibitors, or a combination of these, in a selected panNET population., Competing Interests: C.Pratilas (Genentech, consultancy).

Background: This meta-analysis was conducted to assess the risk of dermatological toxicities of combined BRAF and MEK inhibition versus BRAF inhibition alone in melanoma patients., Methods: We considered relevant prospective randomized phase I, II, and III trials of melanoma patients on the combined BRAF and MEK inhibition versus BRAF inhibition, describing events of rash, photosensitivity reaction (PR), hyperkeratosis (HK), alopecia, cutaneous squamous-cell carcinom(cSCC), skin papilloma(SP), pruritus, and hand-foot syndrome(HFS), as eligible for inclusion., Results: Eight trials comprising 3163 patients were included in the meta-analysis. The relative risks(RRs) of developing all-grade rash with combined BRAF and MEK inhibition versus BRAF inhibition was 1.59 (95%CI, 1.35-1.86, p < 0.00001), HK 0.33(95%CI, 0.16-0.66, p = 0.002), SP 0.09(95%CI, 0.04-0.24, p < 0.00001), alopecia 0.30(95%CI, 0.19-0.48, p < 0.00001), cSCC 0.23(95%CI, 0.17-0.31, p < 0.00001), HFS 0.18(95%CI, 0.13-0.26, p < 0.00001) and PR 0.40(95%CI, 0.26-0.61, p < 0.0001), while the RRs of high-grade dermatological toxicities from all included trials were: rash 0.54(95%CI, 0.20-1.43, p = 0.21), HK 0.18(95%CI, 0.06-0.53, p = 0.002), SP 0.14(95%CI, 0.02-1.16, p = 0.07), alopecia 0.72(95%CI, 0.14-3.62, p = 0.69), cSCC 0.23(95%CI, 0.17-0.33, p < 0.00001), HFS 0.40(95%CI, 0.08-2.06, p = 0.27), and PR 0.14(95%CI, 0.04-0.51, p = 0.003), respectly., Conclusion: Our analysis of data has demonstrated that combined BRAF and MEK inhibitor-based treatment is associated with an increased risk of all-grade rash and a decreased risk of all-grade and high-grade HK, SP, alopecia, cSCC, HFS, and PR compared with single BRAF inhibitor alone in melanoma patients. Appropriate prevention and management are recommended.

Treatment of advanced melanoma has undergone a paradigm shift over the last 10-15 years. The frustrating results of studies on medical treatment ten years ago have been replaced by studies constantly improving survival in patients with advanced melanoma. Immune checkpoint inhibitors belong to one group of treatments and targeted therapy to another. Fifty percent of melanomas are BRAF mutation positive. Normally, the mitogen activated protein kinase or MAP kinase (Ras-BRAF-MEK-Erk chain) pathways translate external signals to intracellular growth and proliferation. In BRAF mutated melanoma cells, the mutated BRAF kinase is excessively active leading to autonomous proliferation and cancerous growth. This kinase can be blocked by BRAF-inhibitors. If given to BRAF negative melanoma patients, it may lead to disease progression because Ras is not inhibited in these cells. Development of Squamous cell carcinomas as a serious adverse event to BRAF inhibition may be caused by similar mechanisms in non BRAF mutated keratinocytes. A spontaneous and paradoxical loss of effect is seen with BRAF inhibitors due to various ways melanoma cells bypass BRAF. This is somewhat counteracted by the addition of a MEK1/2 inhibitor. Overall progression-free survival has increased from a median of two months for chemotherapy, via 7-8 months for BRAF inhibitor to 10-14 months for newer BRAF and MEK inhibitor combination therapy., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Introduction: This study aimed to characterize the tumor-infiltrating immune cells population in Kras/tumor protein 53 (Trp53)-driven lung tumors and to evaluate the combinatorial antitumor effect with MEK inhibitor (MEKi), trametinib, and immunomodulatory monoclonal antibodies (mAbs) targeting either programmed death -1 (PD-1) or programmed cell death ligand 1 (PD-L1) in vivo., Methods: Trp53 FloxFlox ;Kras G12D/+ ;Rosa26 LSL-Luciferase/LSL-Luciferase (PKL) genetically engineered mice were used to develop autochthonous lung tumors with intratracheal delivery of adenoviral Cre recombinase. Using these tumor-bearing lungs, tumor-infiltrating immune cells were characterized by both mass cytometry and flow cytometry. PKL-mediated immunocompetent syngeneic and transgenic lung cancer mouse models were treated with MEKi alone as well as in combination with either anti-PD-1 or anti-PD-L1 mAbs. Tumor growth and survival outcome were assessed. Finally, immune cell populations within spleens and tumors were evaluated by flow cytometry and immunohistochemistry., Results: Myeloid-derived suppressor cells (MDSCs) were significantly augmented in PKL-driven lung tumors compared to normal lungs of tumor-free mice. PD-L1 expression appeared to be highly positive in both lung tumor cells and, particularly MDSCs. The combinatory administration of MEKi with either anti-PD-1 or anti-PD-L1 mAbs synergistically increased antitumor response and survival outcome compared with single-agent therapy in both the PKL-mediated syngeneic and transgenic lung cancer models. Theses combinational treatments resulted in significant increases of tumor-infiltrating CD8 + and CD4 + T cells, whereas attenuation of CD11b + /Gr-1 high MDSCs, in particular, Ly6G high polymorphonuclear-MDSCs in the syngeneic model., Conclusions: These findings suggest a potential therapeutic approach for untargetable Kras/p53-driven lung cancers with synergy between targeted therapy using MEKi and immunotherapies., (Copyright © 2019 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.)