Epigenetic modulation reveals differentiation state specificity of oncogene addiction

AbstractHyperactivation of the MAPK signaling pathway motivates the clinical use of MAPK inhibitors for BRAF-mutant melanomas. Heterogeneity in differentiation state due to epigenetic plasticity, however, results in cell-to-cell variability in the state of MAPK dependency, diminishing the efficacy of MAPK inhibitors. To identify key regulators of such variability, we screen 276 epigenetic-modifying compounds, individually or combined with MAPK inhibitors, across genetically diverse and isogenic populations of melanoma cells. Following single-cell analysis and multivariate modeling, we identify three classes of epigenetic inhibitors that target distinct epigenetic states associated with either one of the lysine-specific histone demethylases Kdm1a or Kdm4b, or BET bromodomain proteins. While melanocytes remain insensitive, the anti-tumor efficacy of each inhibitor is predicted based on melanoma cells’ differentiation state and MAPK activity. Our systems pharmacology approach highlights a path toward identifying actionable epigenetic factors that extend the BRAF oncogene addiction paradigm on the basis of tumor cell differentiation state.

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Epigenetic modulation reveals differentiation state specificity of oncogene addiction

10.1101/2020.05.04.077602 ◽

2020 ◽

Author(s):

Mehwish Khaliq ◽

Mohan Manikkam ◽

Elisabeth D. Martinez ◽

Mohammad Fallahi-Sichani

Keyword(s):

Single Cell Analysis ◽

Melanoma Cells ◽

Mapk Signaling ◽

Histone Demethylases ◽

Oncogene Addiction ◽

Mapk Activity ◽

Bromodomain Proteins ◽

Mapk Inhibitors ◽

Epigenetic Modulation ◽

Cell To Cell Variability

AbstractHyperactivation of the MAPK signaling pathway motivates the clinical use of MAPK inhibitors for BRAF-mutant melanomas. Heterogeneity in differentiation state due to epigenetic plasticity, however, results in cell-to-cell variability in the state of MAPK dependency, diminishing the efficacy of MAPK inhibitors. To identify key regulators of such variability, we screened 276 epigenetic-modifying compounds, individually or combined with MAPK inhibitors, across genetically diverse and isogenic populations of melanoma cells. Following single-cell analysis and multivariate modeling, we identified three classes of epigenetic inhibitors that target distinct epigenetic states associated with either one of the lysine-specific histone demethylases KDM1A or KDM4B, or BET bromodomain proteins. While melanocytes remained insensitive, the anti-tumor efficacy of each inhibitor was predicted based on melanoma cells’ differentiation state and MAPK activity. Our systems pharmacology approach highlights a path toward identifying actionable epigenetic factors that extend the BRAF oncogene addiction paradigm on the basis of tumor cell differentiation state.

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p38α MAPK signaling drives pharmacologically reversible brain and gastrointestinal phenotypes in the SERT Ala56 mouse

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1809137115 ◽

2018 ◽

Vol 115 (43) ◽

pp. E10245-E10254 ◽

Cited By ~ 11

Author(s):

Matthew J. Robson ◽

Meagan A. Quinlan ◽

Kara Gross Margolis ◽

Paula A. Gajewski-Kurdziel ◽

Jeremy Veenstra-VanderWeele ◽

...

Keyword(s):

Social Interactions ◽

P38 Mapk ◽

Treatment Options ◽

Colonic Motility ◽

Mapk Signaling ◽

Autism Spectrum ◽

Mapk Activity ◽

P38α Mapk ◽

P38 Mapk Inhibitors ◽

Mapk Inhibitors

Autism spectrum disorder (ASD) is a common neurobehavioral disorder with limited treatment options. Activation of p38 MAPK signaling networks has been identified in ASD, and p38 MAPK signaling elevates serotonin (5-HT) transporter (SERT) activity, effects mimicked by multiple, hyperfunctional SERT coding variants identified in ASD subjects. Mice expressing the most common of these variants (SERT Ala56) exhibit hyperserotonemia, a biomarker observed in ASD subjects, as well as p38 MAPK-dependent SERT hyperphosphorylation, elevated hippocampal 5-HT clearance, hypersensitivity of CNS 5-HT1A and 5-HT2A/2C receptors, and behavioral and gastrointestinal perturbations reminiscent of ASD. As the α-isoform of p38 MAPK drives SERT activation, we tested the hypothesis that CNS-penetrant, α-isoform–specific p38 MAPK inhibitors might normalize SERT Ala56 phenotypes. Strikingly, 1-week treatment of adult SERT Ala56 mice with MW150, a selective p38α MAPK inhibitor, normalized hippocampal 5-HT clearance, CNS 5-HT1A and 5-HT2A/2C receptor sensitivities, social interactions, and colonic motility. Conditional elimination of p38α MAPK in 5-HT neurons of SERT Ala56 mice restored 5-HT1A and 5-HT2A/2C receptor sensitivities as well as social interactions, mirroring effects of MW150. Our findings support ongoing p38α MAPK activity as an important determinant of the physiological and behavioral perturbations of SERT Ala56 mice and, more broadly, supports consideration of p38α MAPK inhibition as a potential treatment for core and comorbid phenotypes present in ASD subjects.

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Involvement of PI3K and MAPK Signaling in bcl-2-induced Vascular Endothelial Growth Factor Expression in Melanoma Cells

Molecular Biology of the Cell ◽

10.1091/mbc.e04-12-1087 ◽

2005 ◽

Vol 16 (9) ◽

pp. 4153-4162 ◽

Cited By ~ 61

Author(s):

Daniela Trisciuoglio ◽

Angela Iervolino ◽

Gabriella Zupi ◽

Donatella Del Bufalo

Keyword(s):

Vascular Endothelial Growth Factor ◽

Rna Interference ◽

Growth Factor ◽

Hypoxia Inducible Factor ◽

Melanoma Cells ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Vascular Endothelial ◽

Mapk Inhibitors ◽

Endothelial Growth Factor

We have previously demonstrated that bcl-2 overexpression in tumor cells exposed to hypoxia increases the expression of vascular endothelial growth factor (VEGF) gene through the hypoxia-inducible factor-1 (HIF-1). In this article, we demonstrate that exposure of bcl-2 overexpressing melanoma cells to hypoxia induced phosphorylation of AKT and extracellular signal-regulated kinase (ERK)1/2 proteins. On the contrary, no modulation of these pathways by bcl-2 was observed under normoxic conditions. When HIF-1α expression was reduced by RNA interference, AKT and ERK1/2 phosphorylation were still induced by bcl-2. Pharmacological inhibition of mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) signaling pathways reduced the induction of VEGF and HIF-1 in response to bcl-2 overexpression in hypoxia. No differences were observed between control and bcl-2-overexpressing cells in normoxia, in terms of VEGF protein secretion and in response to PI3K and MAPK inhibitors. We also demonstrated that RNA interference-mediated down-regulation of bcl-2 expression resulted in a decrease in the ERK1/2 phosphorylation and VEGF secretion only in bcl-2-overexpressing cell exposed to hypoxia but not in control cells. In conclusion, our results indicate, for the first time, that bcl-2 synergizes with hypoxia to promote expression of angiogenesis factors in melanoma cells through both PI3K- and MAPK-dependent pathways.

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Quantitative Tyr Phosphoproteomic Analyses Identify Cholesterol as a Master Regulator of Tumor Adaptive Resistance to MAPK Inhibition

10.1101/2021.05.20.444617 ◽

2021 ◽

Author(s):

Yonghao Yu ◽

Xu-Dong Wang ◽

Chiho Kim ◽

Yajie Zhang ◽

Smita Rindhe ◽

...

Keyword(s):

Rational Design ◽

Cholesterol Metabolism ◽

Mapk Pathway ◽

Melanoma Cells ◽

Mapk Signaling ◽

Binding Motif ◽

Master Regulator ◽

Durable Response ◽

Mapk Inhibitors ◽

Targeted Inhibition

Although targeted inhibition of the MAPK pathway has achieved remarkable patient responses in many cancers with MAPK hyperactivation, the development of resistance has remained a critical challenge. Besides genomic resistance mechanisms, adaptive tumor response also underlies the resistance to targeted MAPK inhibitors. It is being increasingly appreciated that such bypass mechanisms often lead to the activation of many pro-survival kinases, which complicates the rational design of combination therapies. Here we performed global tyrosine phosphoproteomic (pTyr) analyses and demonstrated that targeted inhibition of MAPK signaling in melanoma cells leads to a profound remodeling of the pTyr proteome. Intriguingly, many of these kinases contain a cholesterol binding motif, suggesting that altered cholesterol metabolism might drive, in a coordinated fashion, the activation of these kinases. Indeed, we found a dramatic accumulation of intracellular cholesterol in melanoma cells (with BRAFV600E mutations) and non-small cell lung cancer cells (with KRASG12C mutations) treated with MAPK and KRASG12C inhibitors, respectively. Importantly, depletion of cholesterol not only prevented the MAPK inhibition-induced feedback activation of pTyr singling but also enhanced the cytotoxic effects of MAPK inhibitors, both in vitro and in vivo. Taken together, our findings provide the evidence suggesting that cholesterol functions as a master regulator of the tumor adaptive response to targeted MAPK inhibitors. These results also suggest that MAPK inhibitors could be combined with cholesterol-lowering agents to achieve a more complete and durable response in tumors with hyperactive MAPK signaling.

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Targeting Genome Stability in Melanoma—A New Approach to an Old Field

International Journal of Molecular Sciences ◽

10.3390/ijms22073485 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3485

Author(s):

Marta Osrodek ◽

Michal Wozniak

Keyword(s):

Genome Stability ◽

Genome Instability ◽

Checkpoint Inhibitors ◽

Mapk Pathway ◽

Rapid Development ◽

Melanoma Cells ◽

Old Field ◽

Number Of Patients ◽

Recent Developments ◽

Mapk Inhibitors

Despite recent groundbreaking advances in the treatment of cutaneous melanoma, it remains one of the most treatment-resistant malignancies. Due to resistance to conventional chemotherapy, the therapeutic focus has shifted away from aiming at melanoma genome stability in favor of molecularly targeted therapies. Inhibitors of the RAS/RAF/MEK/ERK (MAPK) pathway significantly slow disease progression. However, long-term clinical benefit is rare due to rapid development of drug resistance. In contrast, immune checkpoint inhibitors provide exceptionally durable responses, but only in a limited number of patients. It has been increasingly recognized that melanoma cells rely on efficient DNA repair for survival upon drug treatment, and that genome instability increases the efficacy of both MAPK inhibitors and immunotherapy. In this review, we discuss recent developments in the field of melanoma research which indicate that targeting genome stability of melanoma cells may serve as a powerful strategy to maximize the efficacy of currently available therapeutics.

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Antitumor and apoptotic effects of quercetin on human melanoma cells involving JNK/P38 MAPK signaling activation

European Journal of Pharmacology ◽

10.1016/j.ejphar.2019.172568 ◽

2019 ◽

Vol 860 ◽

pp. 172568 ◽

Cited By ~ 12

Author(s):

Sung-Hyun Kim ◽

Eun-Seon Yoo ◽

Joong-Seok Woo ◽

So-Hee Han ◽

Jae-Han Lee ◽

...

Keyword(s):

P38 Mapk ◽

Melanoma Cells ◽

Mapk Signaling ◽

Human Melanoma ◽

Human Melanoma Cells ◽

Signaling Activation ◽

Apoptotic Effects

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Gab1 and SHP-2 promote Ras/MAPK regulation of epidermal growth and differentiation

The Journal of Cell Biology ◽

10.1083/jcb.200205017 ◽

2002 ◽

Vol 159 (1) ◽

pp. 103-112 ◽

Cited By ~ 57

Author(s):

Ti Cai ◽

Keigo Nishida ◽

Toshio Hirano ◽

Paul A. Khavari

Keyword(s):

Epidermal Cell ◽

Mapk Signaling ◽

Dominant Negative ◽

Mapk Activity ◽

Ras Activation ◽

Proliferation And Differentiation ◽

Epidermal Proliferation ◽

Epidermal Growth ◽

Docking Protein

În epidermis, Ras can influence proliferation and differentiation; however, regulators of epidermal Ras function are not fully characterized, and Ras effects on growth and differentiation are controversial. EGF induced Ras activation in epidermal cells along with phosphorylation of the multisubstrate docking protein Gab1 and its binding to SHP-2. Expression of mutant Gab1Y627F deficient in SHP-2 binding or dominant-negative SHP-2C459S reduced basal levels of active Ras and downstream MAPK proteins and initiated differentiation. Differentiation triggered by both Gab1Y627F and SHP-2C459S could be blocked by coexpression of active Ras, consistent with Gab1 and SHP-2 action upstream of Ras in this process. To study the role of Gab1 and SHP-2 in tissue, we generated human epidermis overexpressing active Gab1 and SHP-2. Both proteins stimulated proliferation. In contrast, Gab1Y627F and SHP-2C459S inhibited epidermal proliferation and enhanced differentiation. Consistent with a role for Gab1 and SHP-2 in sustaining epidermal Ras/MAPK activity, Gab1−/− murine epidermis displayed lower levels of active Ras and MAPK with postnatal Gab1−/− epidermis, demonstrating the hypoplasia and enhanced differentiation seen previously with transgenic epidermal Ras blockade. These data provide support for a Ras role in promoting epidermal proliferation and opposing differentiation and indicate that Gab1 and SHP-2 promote the undifferentiated epidermal cell state by facilitating Ras/MAPK signaling.

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Identification of ACA-28, a 1′-acetoxychavicol acetate analogue compound, as a novel modulator of ERK MAPK signaling, which preferentially kills human melanoma cells

Genes to Cells ◽

10.1111/gtc.12499 ◽

2017 ◽

Vol 22 (7) ◽

pp. 608-618 ◽

Cited By ~ 7

Author(s):

Ryosuke Satoh ◽

Kanako Hagihara ◽

Kazuki Matsuura ◽

Yoshiaki Manse ◽

Ayako Kita ◽

...

Keyword(s):

Melanoma Cells ◽

Mapk Signaling ◽

Human Melanoma ◽

Erk Mapk ◽

Human Melanoma Cells

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Regulation of Raf-1-dependent signaling during early Xenopus development.

Molecular and Cellular Biology ◽

10.1128/mcb.15.12.6686 ◽

1995 ◽

Vol 15 (12) ◽

pp. 6686-6693 ◽

Cited By ~ 21

Author(s):

A M MacNicol ◽

A J Muslin ◽

E L Howard ◽

A Kikuchi ◽

M C MacNicol ◽

...

Keyword(s):

Cell Cycle ◽

Cell Cycle Progression ◽

Mapk Pathway ◽

Mapk Signaling ◽

Embryonic Cell ◽

Cycle Progression ◽

Mapk Activity ◽

Cytostatic Factor ◽

Differentiation And Proliferation

The Raf-1 gene product is activated in response to cellular stimulation by a variety of growth factors and hormones. Raf-1 activity has been implicated in both cellular differentiation and proliferation. We have examined the regulation of the Raf-1/MEK/MAP kinase (MAPK) pathway during embryonic development in the frog Xenopus laevis. We report that Raf-1, MEK, and MAPK activities are turned off following fertilization and remain undetectable up until blastula stages (stage 8), some 4 h later. Tight regulation of the Raf-1/MEK/MAPK pathway following fertilization is crucial for embryonic cell cycle progression. Inappropriate reactivation of MAPK activity by microinjection of oncogenic Raf-1 RNA results in metaphase cell cycle arrest and, consequently, embryonic lethality. Our findings demonstrate an absolute requirement, in vivo, for inactivation of the MAPK signaling pathway to allow normal cell cycle progression during the period of synchronous cell divisions which occur following fertilization. Further, we show that cytostatic factor effects are mediated through MEK and MAPK.

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