scholarly journals A screen for combination therapies inBRAF/NRASwild type melanoma identifies nilotinib plus MEK inhibitor as a synergistic combination

2017 ◽  
Author(s):  
Marco Ranzani ◽  
Kristel Kemper ◽  
Magali Michaut ◽  
Oscar Krijgsman ◽  
Nanne Aben ◽  
...  

AbstractDespite recent therapeutic advances in the management ofBRAFV600-mutant melanoma, there is still a compelling need for more effective treatments for patients who developedBRAF/NRASwild type disease. Since the activity of single targeted agents is limited by innate and acquired resistance, we performed a high-throughput drug screen using 180 drug combinations to generate over 18,000 viability curves, with the aim of identifying agents that synergise to killBRAF/NRASwild type melanoma cells. From this screen we observed strong synergy between the tyrosine kinase inhibitor nilotinib and MEK inhibitors and validated this combination in an independent cell line collection. We found that AXL expression was associated with synergy to the nilotinib/MEK inhibitor combination, and that both drugs work in concert to suppress pERK. This finding was supported by genome-wide CRISPR screening which revealed that resistance mechanisms converge on regulators of the MAPK pathway. Finally, we validated the synergy of nilotinib/trametinib combinationin vivousing patient-derived xenografts. Our results indicate that a nilotinib/MEK inhibitor combination may represent an effective therapy inBRAF/NRASwild type melanoma patients.

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii62-ii62
Author(s):  
Elisa Izquierdo ◽  
Diana Carvalho ◽  
Alan Mackay ◽  
Sara Temelso ◽  
Jessica K R Boult ◽  
...  

Abstract The survival of children with diffuse intrinsic pontine glioma (DIPG) remains dismal, with new treatments desperately needed. In the era of precision medicine, targeted therapies represent an exciting treatment opportunity, yet resistance can rapidly emerge, playing an important role in treatment failure. In a prospective biopsy-stratified clinical trial, we combined detailed molecular profiling (methylation BeadArray, exome, RNAseq, phospho-proteomics) linked to drug screening in newly-established patient-derived models of DIPG in vitro and in vivo. We identified a high degree of in vitro sensitivity to the MEK inhibitor trametinib (GI50 16-50nM) in samples, which harboured genetic alterations targeting the MAPK pathway, including the non-canonical BRAF_G469V mutation, and those affecting PIK3R1 and NF1. However, treatment of PDX models and of a patient with trametinib at relapse failed to elicit a significant response. We generated trametinib-resistant clones (62-188-fold, GI50 2.4–5.2µM) in the BRAF_G469V model through continuous drug exposure, and identified acquired mutations in MEK1/2 (MEK1_K57N, MEK1_I141S and MEK2_I115N) with sustained pathway up-regulation. These cells showed the hallmarks of mesenchymal transition, and expression signatures overlapping with inherently trametinib-insensitive primary patient-derived cells that predicted an observed sensitivity to dasatinib. Combinations of trametinib with dasatinib and the downstream ERK inhibitor ulixertinib showed highly synergistic effects in vitro. These data highlight the MAPK pathway as a therapeutic target in DIPG, and show the importance of parallel resistance modelling and rational combinatorial treatments likely to be required for meaningful clinical translation.


2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii414-iii414
Author(s):  
Elisa Izquierdo ◽  
Diana Carvalho ◽  
Alan Mackay ◽  
Sara Temelso ◽  
Jessica K R Boult ◽  
...  

Abstract The survival of children with DIPG remains dismal, with new treatments desperately needed. In the era of precision medicine, targeted therapies represent an exciting treatment opportunity, yet resistance can rapidly emerge, playing an important role in treatment failure. In a prospective biopsy-stratified clinical trial (BIOMEDE), we combined detailed molecular profiling (methylation BeadArray, exome, RNAseq, phospho-proteomics) linked to drug screening in newly-established patient-derived models of DIPG in vitro and in vivo. We identified a high degree of in vitro sensitivity to the MEK inhibitor trametinib (GI50 16-50nM) in samples which harboured genetic alterations targeting the MAPK pathway, including the non-canonical BRAF_G469V mutation, and those affecting PIK3R1. Treatment of PDX models and the patient with trametinib at relapse, however, failed to elicit a significant response. We generated trametinib-resistant clones (62-188-fold, GI50 2.4–5.2µM) in the BRAF_G469V model through continuous drug exposure, and identified acquired mutations in MEK1/2 (MEK1_K57N, MEK1_I141S and MEK2_I115N) with sustained pathway up-regulation. These cells showed the hallmarks of mesenchymal transition, with overexpression of key proteins involved in invasion/migration, such as collagen-family proteins, integrins, MMPs and AHNAK2, amongst others. Resistant clones were conversely sensitive to the upstream receptor tyrosine kinase inhibitor dasatinib (GI50 36-93nM), and combinations of trametinib with dasatinib and the downstream ERK inhibitor ulixertinib showed synergistic effects in vitro. These data highlight the MAPK pathway as a therapeutic target in DIPG, and show the importance of parallel resistance modelling and rational combinatorial treatments likely to be required for meaningful clinical translation.


Author(s):  
S. Napolitano ◽  
N. Matrone ◽  
A. L. Muddassir ◽  
G. Martini ◽  
A. Sorokin ◽  
...  

Abstract Background Molecular mechanisms driving acquired resistance to anti-EGFR therapies in metastatic colorectal cancer (mCRC) are complex but generally involve the activation of the downstream RAS-RAF-MEK-MAPK pathway. Nevertheless, even if inhibition of EGFR and MEK could be a strategy for overcoming anti-EGFR resistance, its use is limited by the development of MEK inhibitor (MEKi) resistance. Methods We have generated in vitro and in vivo different CRC models in order to underline the mechanisms of MEKi resistance. Results The three different in vitro MEKi resistant models, two generated by human CRC cells quadruple wild type for KRAS, NRAS, BRAF, PI3KCA genes (SW48-MR and LIM1215-MR) and one by human CRC cells harboring KRAS mutation (HCT116-MR) showed features related to the gene signature of colorectal cancer CMS4 with up-regulation of immune pathway as confirmed by microarray and western blot analysis. In particular, the MEKi phenotype was associated with the loss of epithelial features and acquisition of mesenchymal markers and morphology. The change in morphology was accompanied by up-regulation of PD-L1 expression and activation of EGFR and its downstream pathway, independently to RAS mutation status. To extend these in vitro findings, we have obtained mouse colon cancer MC38- and CT26-MEKi resistant syngeneic models (MC38-MR and CT26-MR). Combined treatment with MEKi, EGFR inhibitor (EGFRi) and PD-L1 inhibitor (PD-L1i) resulted in a marked inhibition of tumor growth in both models. Conclusions These results suggest a strategy to potentially improve the efficacy of MEK inhibition by co-treatment with EGFR and PD-L1 inhibitors via modulation of host immune responses.


2019 ◽  
pp. 1-3
Author(s):  
Qiang Zuo ◽  
Yanlin Yu

Although targeted treatment by BRAF inhibitors (BRAFi) achieved a remarkable clinical response for patients with BRAF mutation, the strength of efficacy is short and limited by acquired drug resistance [1]. Recent studies identified many mechanisms of acquired resistance to BRAFi, such as mutations in NRAS or MEK1 and overexpression of COT, EGFR, PDGFRβ, IGF1R or MET, lead the reactivation of MAPK pathway and drive the cell proliferation, suggesting that co-targeting this hyperactivated survival pathway by combination inhibitors might gain the maximum clinical benefits for melanoma patients [2]. Based on these findings, FDA approved the combination of dabrafenib (BRAFi) with trametinib (MEK inhibitor) or vemurafenib (BRAFi) with cobimetinib (MEK inhibitor) to inhibit the MAPK signaling pathway in 2014 and 2015 more effectively. Indeed, the dual inhibitors of MEK and mutant BRAF kinases have shown a higher overall survival rate and exciting results in initial tumor response in clinical.


Cancers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 6
Author(s):  
Silvia La Monica ◽  
Claudia Fumarola ◽  
Daniele Cretella ◽  
Mara Bonelli ◽  
Roberta Minari ◽  
...  

Abemaciclib is an inhibitor of cyclin-dependent kinases (CDK) 4 and 6 that inhibits the transition from the G1 to the S phase of the cell cycle by blocking downstream CDK4/6-mediated phosphorylation of Rb. The effects of abemaciclib alone or combined with the third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) osimertinib were examined in a panel of PC9 and HCC827 osimertinib-resistant non-small cell lung cancer (NSCLC) cell lines carrying EGFR-dependent or -independent mechanisms of intrinsic or acquired resistance. Differently from sensitive cells, all the resistant cell lines analyzed maintained p-Rb, which may be considered as a biomarker of osimertinib resistance and a potential target for therapeutic intervention. In these models, abemaciclib inhibited cell growth, spheroid formation, colony formation, and induced senescence, and its efficacy was not enhanced in the presence of osimertinib. Interestingly, in osimertinib sensitive PC9, PC9T790M, and H1975 cells the combination of abemaciclib with osimertinib significantly inhibited the onset of resistance in long-term experiments. Our findings provide a preclinical support for using abemaciclib to treat resistance in EGFR mutated NSCLC patients progressed to osimertinib either as single treatment or combined with osimertinib, and suggest the combination of osimertinib with abemaciclib as a potential approach to prevent or delay osimertinib resistance in first-line treatment.


2021 ◽  
Vol 39 (15_suppl) ◽  
pp. TPS3616-TPS3616
Author(s):  
Tanios S. Bekaii-Saab ◽  
Eric Van Cutsem ◽  
Antonio Cubillo ◽  
Caroline Petorin-Lesens ◽  
Nuria Rodriguez-Salas ◽  
...  

TPS3616 Background: METamp is a secondary, or co-driving, genetic change in pts with mCRC and acquired resistance to anti-EGFR therapy, which can contribute to disease progression. In EGFR-resistant pts with mCRC and METamp, MET inhibition + an anti-EGFR agent may achieve disease control by targeting emerging MET pathway activation and maintaining EGFR pathway inhibition. Tepotinib is an oral, once-daily, highly selective, potent MET tyrosine kinase inhibitor (TKI), recently approved in the US for NSCLC harboring MET exon 14 skipping. Tepotinib + gefitinib demonstrated improved outcomes in pts with EGFR-mutant METamp NSCLC and acquired EGFR TKI resistance vs chemotherapy (INSIGHT: NCT01982955). In these pts, progression-free survival (PFS) was 16.6 vs 4.2 months (HR = 0.13; 90% CI: 0.04, 0.43) and overall survival (OS) was 37.3 vs 13.1 months (HR = 0.08; 90% CI: 0.01, 0.51). In pts with mCRC and acquired resistance to anti-EGFR antibody therapy due to METamp, tepotinib + anti-EGFR antibody cetuximab may be active and provide an effective therapeutic option. Methods: This Phase II, multicenter, single-arm, open-label study will assess preliminary safety and tolerability, antitumor activity, and explore pharmacokinetic (PK) profiles of tepotinib + cetuximab in pts with RAS/BRAF wild-type left-sided mCRC and acquired resistance to anti-EGFR antibody-targeted therapy due to METamp (NCT04515394). A safety run-in (6–12 pts) will evaluate the recommended Phase II dose of tepotinib to be used in combination with cetuximab (endpoint: dose-limiting toxicities). Enrollment is based on a confirmed advanced left-sided CRC diagnosis ( RAS/BRAF wild-type), documented previous anti-EGFR therapy and acquired resistance on most recent anti-EGFR antibody and METamp confirmed by liquid and/or tissue biopsy. Pts must be ≥18 years old, have ECOG PS of 0/1 and normal organ function. The study will screen sufficient pts to account for setting-specific heterogenecity in reported METamp incidence. Approximately 42 pts are planned to receive study treatment: ̃22 in Cohort A (second-line, outside US) and 20 in Cohort B (≥third-line, US only). Primary endpoint: investigator-assessed objective response (RECIST 1.1). Secondary endpoints are investigator-assessed duration of response (DoR), PFS (RECIST 1.1) and OS, tolerability and safety (NCI-CTCAE v5.0), and cetuximab immunogenicity (measured by antidrug antibody assays at the start and end of treatment). Additional endpoints include assessment of tepotinib and cetuximab PK profiles, and expression of biomarkers of resistance (from blood and/or tissue samples). Retrospective assessment of best overall response, DoR and PFS by an independent review committee may be conducted. No formal statistical hypothesis will be tested in this exploratory study. Clinical trial information: NCT04515394.


Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Kirti Kandhwal Chahal ◽  
Jie Li ◽  
Irina Kufareva ◽  
Donald Durden ◽  
Robert Wechsler Reya ◽  
...  

Abstract INTRODUCTION Dysregulation of the 7-transmembrane receptors Smoothened (SMO) and other components of the Hedgehog (Hh) signaling pathway causes several cancers, including medulloblastoma (MB) and glioblastoma. However, SMO-specific antagonists produced mixed results in clinical trials, marked by a limited efficacy and a high rate of acquired resistance in tumors. METHODS Computational modeling of protein docking sites, analytical configuration modeling of crystallographic data, and in Vitro and in Vivo xenograft experiments. RESULTS Using computational modeling of SMO structure, we discovered that Nilotinib, an FDA-approved receptor tyrosine kinase inhibitor, directly binds to SMO. Furthermore, Nilotinib was more efficacious than the SMO-specific antagonist Vismodegib in inhibiting cell growth and Gli-1 mRNA and protein levels in Hh-dependent MB cells and glioblastoma cells. It also reduced tumor growth in the Hh-dependent MB and glioblastoma mouse xenograft models. These results indicate that in addition to its ability to inhibit several tyrosine kinase-mediated proliferative pathways, Nilotinib is active against the Hh pathway. CONCLUSION The newly discovered extension of Nilotinib target profile holds promise for the treatment of Hh-dependent cancers. It also calls for comprehensive characterization of pharmacology for other drugs and incorporation of their multitarget profiles into drug-disease matching criteria for personalized medicine.


2004 ◽  
Vol 286 (1) ◽  
pp. G95-G101 ◽  
Author(s):  
S. P. Rao ◽  
Z. Sellers ◽  
D. L. Crombie ◽  
D. L. Hogan ◽  
E. A. Mann ◽  
...  

Luminal acidification provides the strongest physiological stimulus for duodenal [Formula: see text] secretion. Various neurohumoral mechanisms are believed to play a role in acid-stimulated [Formula: see text] secretion. Previous studies in the rat and human duodenum have shown that guanylin and Escherichia coli heat-stable toxin, both ligands of the transmembrane guanylyl cyclase receptor [guanylate cyclase C (GC-C)], are potent stimulators for duodenal [Formula: see text] secretion. We postulated that the GC-C receptor plays an important role in acid-stimulated [Formula: see text] secretion. In vivo perfusion studies performed in wild-type (WT) and GC-C knockout (KO) mice indicated that acid-stimulated duodenal [Formula: see text] secretion was significantly decreased in the GC-C KO animals compared with the WT counterparts. Pretreatment with PD-98059, an MEK inhibitor, resulted in attenuation of duodenal [Formula: see text] secretion in response to acid stimulation in the WT mice with no further effect in the KO mice. In vitro cGMP generation studies demonstrated a significant and comparable increase in cGMP levels on acid exposure in the duodenum of both WT and KO mice. In addition, a rapid, time-dependent phosphorylation of ERK was observed with acid exposure in the duodenum of WT mice, whereas a marked attenuation in ERK phosphorylation was observed in the KO animals despite equivalent levels of ERK in both groups of animals. On the basis of these studies, we conclude that transmembrane GC-C is a key mediator of acid-stimulated duodenal [Formula: see text] secretion. Furthermore, ERK phosphorylation may be an important intracellular mediator of duodenal [Formula: see text] secretion.


2017 ◽  
Vol 214 (6) ◽  
pp. 1691-1710 ◽  
Author(s):  
Helen L. Young ◽  
Emily J. Rowling ◽  
Mattia Bugatti ◽  
Emanuele Giurisato ◽  
Nadia Luheshi ◽  
...  

Mitogen-activated protein kinase (MAPK) pathway antagonists induce profound clinical responses in advanced cutaneous melanoma, but complete remissions are frustrated by the development of acquired resistance. Before resistance emerges, adaptive responses establish a mutation-independent drug tolerance. Antagonizing these adaptive responses could improve drug effects, thereby thwarting the emergence of acquired resistance. In this study, we reveal that inflammatory niches consisting of tumor-associated macrophages and fibroblasts contribute to treatment tolerance through a cytokine-signaling network that involves macrophage-derived IL-1β and fibroblast-derived CXCR2 ligands. Fibroblasts require IL-1β to produce CXCR2 ligands, and loss of host IL-1R signaling in vivo reduces melanoma growth. In tumors from patients on treatment, signaling from inflammatory niches is amplified in the presence of MAPK inhibitors. Signaling from inflammatory niches counteracts combined BRAF/MEK (MAPK/extracellular signal–regulated kinase kinase) inhibitor treatment, and consequently, inhibiting IL-1R or CXCR2 signaling in vivo enhanced the efficacy of MAPK inhibitors. We conclude that melanoma inflammatory niches adapt to and confer drug tolerance toward BRAF and MEK inhibitors early during treatment.


Sign in / Sign up

Export Citation Format

Share Document