RESUMEN

Mitogen-activated protein kinase kinase (MKK), the key element of the Mitogen-activated protein kinase (MAPK) signaling pathway, is crucial for the immune response to adverse environments in aquatic animals. Nevertheless, there is limited information regarding the role of the MKK gene family in mollusks. In our study, genome data and transcriptome were used to identify four MKK genes (CnMKK4, CnMKK5, CnMKK6, and CnMKK7) in the noble scallop. The result of the gene structure, motif analysis, and phylogenetic tree revealed that MKK genes are relatively conserved in bivalves. Moreover, four CnMKK genes were significantly highly expressed in immune-related tissues, suggesting that CnMKKs may related to bivalve immunity. Furthermore, CnMKK6 and CgMKK4 were significantly differentially expressed (P < 0.05) under 24 h of temperature stress, and all CnMKKs were significantly differentially expressed (P < 0.05) under 24 h of Vibrio parahaemolyticus infection. These results showed that the CnMKKs may have a significant impact under biotic and abiotic stresses. In conclusion, the result of the CnMKKs provides valuable insights into comprehending the function of MKK genes in mollusks.

Asunto(s)

Pectinidae , Filogenia , Estrés Fisiológico , Vibrio parahaemolyticus , Animales , Pectinidae/genética , Pectinidae/microbiología , Pectinidae/inmunología , Pectinidae/fisiología , Vibrio parahaemolyticus/fisiología , Estrés Fisiológico/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Temperatura

RESUMEN

Epithelioid glioblastoma (eGB), a very aggressive and rare brain tumour, is associated with a dismal median overall survival. Effective therapies for patients with eGB, particularly with leptomeningeal dissemination, are still lacking. Here, we describe a case of a 25-year-old male diagnosed with an intramedullary cervical tumour with subsequent leptomeningeal disease. Histopathology identified a highly necrotising, epithelioid-type tumour with high cell density, most compatible with the diagnosis of an eGB. DNA analysis revealed an unprecedented B-Raf protooncogene, serine/threonine kinase (BRAF) gene variant in exon 15 (ENST00000288602.6, c.1799_1810delinsATG, p.(V600_W604delinsDG)), triggering activation of the mitogen-activated protein kinase (MAPK) pathway. Consequently, we initiated MAPK inhibitor (MAPKi) therapy, utilizing a combination of BRAF and mitogen-activated protein kinase kinase (MEK) inhibitors. Liquid chromatography-tandem mass spectrometry analysis confirmed the drugs' presence in the patient's cerebrospinal fluid, indicating their capacity to cross the blood-brain barrier. Remarkably, the patient responded very well to therapy and transitioned from a near-comatose state to significantly improved health, sustained for over three months. This study highlights that MAPKi, particularly targeted towards novel BRAFV600 mutations, might offer promising advancements in eGB treatment strategies.

Asunto(s)

Neoplasias Encefálicas , Glioblastoma , Mutación , Inhibidores de Proteínas Quinasas , Proteínas Proto-Oncogénicas B-raf , Humanos , Proteínas Proto-Oncogénicas B-raf/genética , Masculino , Adulto , Glioblastoma/genética , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética

RESUMEN

BACKGROUND: T-LAK cell-oriented protein kinase (TOPK) strongly promotes the malignant proliferation of cancer cells and is recognized as a promising biomarker of tumor progression. Psoriasis is a common inflammatory skin disease featured by excessive proliferation of keratinocytes. Although we have previously reported that topically inhibiting TOPK suppressed psoriatic manifestations in psoriasis-like model mice, the exact role of TOPK in psoriatic inflammation and the underlying mechanism remains elusive. METHODS: GEO datasets were analyzed to investigate the association of TOPK with psoriasis. Skin immunohistochemical (IHC) staining was performed to clarify the major cells expressing TOPK. TOPK conditional knockout (cko) mice were used to investigate the role of TOPK-specific deletion in IMQ-induced psoriasis-like dermatitis in mice. Flow cytometry was used to analyze the alteration of psoriasis-related immune cells in the lesional skin. Next, the M5-induced psoriasis cell model was used to identify the potential mechanism by RNA-seq, RT-RCR, and western blotting. Finally, the neutrophil-neutralizing antibody was used to confirm the relationship between TOPK and neutrophils in psoriasis-like dermatitis in mice. RESULTS: We found that TOPK levels were strongly associated with the progression of psoriasis. TOPK was predominantly increased in the epidermal keratinocytes of psoriatic lesions, and conditional knockout of TOPK in keratinocytes suppressed neutrophils infiltration and attenuated psoriatic inflammation. Neutrophils deletion by neutralizing antibody greatly diminished the suppressive effect of TOPK cko in psoriasis-like dermatitis in mice. In addition, topical application of TOPK inhibitor OTS514 effectively attenuated already-established psoriasis-like dermatitis in mice. Mechanismly, RNA-seq revealed that TOPK regulated the expression of some genes in the IL-17 signaling pathway, such as neutrophils chemokines CXCL1, CXCL2, and CXCL8. TOPK modulated the expression of neutrophils chemokines via activating transcription factors STAT3 and NF-κB p65 in keratinocytes, thereby promoting neutrophils infiltration and psoriasis progression. CONCLUSIONS: This study identified a crucial role of TOPK in psoriasis by regulating neutrophils infiltration, providing new insights into the pathogenesis of psoriasis.

Asunto(s)

Queratinocitos , Quinasas de Proteína Quinasa Activadas por Mitógenos , Infiltración Neutrófila , Psoriasis , Animales , Humanos , Ratones , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Imiquimod , Queratinocitos/patología , Queratinocitos/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Neutrófilos/metabolismo , Neutrófilos/patología , Psoriasis/patología , Psoriasis/genética , Transducción de Señal , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/genética , Regulación hacia Arriba , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo

RESUMEN

Sclerotinia stem rot (SSR), caused by the necrotrophic fungus Sclerotinia sclerotiorum, is one of the most devastating diseases for several major oil-producing crops. Despite its impact, the genetic basis of SSR resistance in plants remains poorly understood. Here, through a genome-wide association study, we identify a key gene, BnaA07. MKK9, that encodes a mitogen-activated protein kinase kinase that confers SSR resistance in oilseed rape. Our functional analyses reveal that BnaA07.MKK9 interacts with BnaC03.MPK3 and BnaC03.MPK6 and phosphorylates them at the TEY activation motif, triggering a signaling cascade that initiates biosynthesis of ethylene, camalexin, and indole glucosinolates, and promotes accumulation of H2O2 and the hypersensitive response, ultimately conferring resistance. Furthermore, variations in the coding sequence of BnaA07.MKK9 alter its kinase activity and improve SSR resistance by ~30% in cultivars carrying the advantageous haplotype. These findings enhance our understanding of SSR resistance and may help engineer novel diversity for future breeding of oilseed rape.

Asunto(s)

Ascomicetos , Brassica napus , Resistencia a la Enfermedad , Estudio de Asociación del Genoma Completo , Enfermedades de las Plantas , Proteínas de Plantas , Ascomicetos/genética , Ascomicetos/patogenicidad , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brassica napus/microbiología , Brassica napus/genética , Brassica napus/inmunología , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Regulación de la Expresión Génica de las Plantas , Fosforilación , Variación Genética

RESUMEN

OBJECTIVE: Exploring the effect of Optimized New Shengmai powder (, ONSMP) on myocardial fibrosis in heart failure (HF) based on rat sarcoma (RAS)/rapidly accelerated fibrosarcoma (RAF)/mitogen-activated protein kinase kinase (MEK)/extracellular regulated protein kinases (ERK) signaling pathway. METHODS: Randomized 70 Sprague-Dawley rats into sham (n = 10) and operation (n = 60) groups, then established the HF rat by ligating the left anterior descending branch of the coronary artery. We randomly divided the operation group rats into the model, ONSMP [including low (L), medium (M), and high (H) dose], and enalapril groups. After the 4-week drug intervention, echocardiography examines the cardiac function and calculates the ratios of the whole/left heart to the rat's body weight. Finally, we observed the degree of myocardial fibrosis by pathological sections, determined myocardium collagen (COL) I and COL Ⅲ content by enzyme-linked immunosorbent assay, detected the mRNA levels of COL I, COL Ⅲ, α-smooth muscle actin (α-SMA), and c-Fos proto-oncogene (c-Fos) by universal real-time, and detected the protein expression of p-RAS, p-RAF, p-MEK1/2, p-ERK1/2, p-ETS-like-1 transcription factor (p-ELK1), p-c-Fos, α-SMA, COL I, and COL Ⅲ by Western blot. RESULTS: ONSMP can effectively improve HF rat's cardiac function, decrease cardiac organ coefficient, COL volume fraction, and COL I/Ⅲ content, down-regulate the mRNA of COL I/Ⅲ, α-SMA and c-Fos, and the protein of p-RAS, p-RAF, p-MEK1/ 2, p-ERK1/2, p-ELK1, c-Fos, COL Ⅰ/Ⅲ, and α-SMA. CONCLUSIONS: ONSMP can effectively reduce myocardial fibrosis in HF rats, and the mechanism may be related to the inhibition of the RAS/RAF/MEK/ERK signaling pathway.

Asunto(s)

Combinación de Medicamentos , Medicamentos Herbarios Chinos , Fibrosis , Insuficiencia Cardíaca , Ratas Sprague-Dawley , Animales , Ratas , Medicamentos Herbarios Chinos/administración & dosificación , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/genética , Fibrosis/tratamiento farmacológico , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/etiología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Miocardio/metabolismo , Miocardio/patología , Sarcoma/tratamiento farmacológico , Sarcoma/genética , Sarcoma/metabolismo , Transducción de Señal/efectos de los fármacos

RESUMEN

BACKGROUND: Low-temperature severely limits the growth and development of Camellia oleifera (C. oleifera). The mitogen-activated protein kinase (MAPK) cascade plays a key role in the response to cold stress. METHODS AND RESULTS: Our study aims to identify MAPK cascade genes in C. oleifera and reveal their roles in response to cold stress. In our study, we systematically identified and analyzed the MAPK cascade gene families of C. oleifera, including their physical and chemical properties, conserved motifs, and multiple sequence alignments. In addition, we characterized the interacting networks of MAPKK kinase (MAPKKK)-MAPK kinase (MAPKK)-MAPK in C. oleifera. The molecular mechanism of cold stress resistance of MAPK cascade genes in wild C. oleifera was analyzed by differential gene expression and real-time quantitative reverse transcription-PCR (qRT-PCR). CONCLUSION: In this study, 21 MAPKs, 4 MAPKKs and 55 MAPKKKs genes were identified in the leaf transcriptome of C. oleifera. According to the phylogenetic results, MAPKs were divided into 4 groups (A, B, C and D), MAPKKs were divided into 3 groups (A, B and D), and MAPKKKs were divided into 2 groups (MEKK and Raf). Motif analysis showed that the motifs in each subfamily were conserved, and most of the motifs in the same subfamily were basically the same. The protein interaction network based on Arabidopsis thaliana (A. thaliana) homologs revealed that MAPK, MAPKK, and MAPKKK genes were widely involved in C. oleifera growth and development and in responses to biotic and abiotic stresses. Gene expression analysis revealed that the CoMAPKKK5/CoMAPKKK43/CoMAPKKK49-CoMAPKK4-CoMAPK8 module may play a key role in the cold stress resistance of wild C. oleifera at a high-elevation site in Lu Mountain (LSG). This study can facilitate the mining and utilization of genetic resources of C. oleifera with low-temperature tolerance.

Asunto(s)

Camellia , Respuesta al Choque por Frío , Regulación de la Expresión Génica de las Plantas , Filogenia , Proteínas de Plantas , Respuesta al Choque por Frío/genética , Camellia/genética , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Quinasas Activadas por Mitógenos/genética , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Sistema de Señalización de MAP Quinasas/genética , Frío , Transcriptoma/genética , Familia de Multigenes , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Perfilación de la Expresión Génica/métodos , Hojas de la Planta/genética

RESUMEN

BACKGROUND: RASopathies are genetic syndromes affecting development and having variable cancer predisposition. These disorders are clinically related and are caused by germline mutations affecting key players and regulators of the RAS-MAPK signaling pathway generally leading to an upregulated ERK activity. Gain-of-function (GOF) mutations in PTPN11, encoding SHP2, a cytosolic protein tyrosine phosphatase positively controlling RAS function, underlie approximately 50% of Noonan syndromes (NS), the most common RASopathy. A different class of these activating mutations occurs as somatic events in childhood leukemias. METHOD: Here, we evaluated the application of a FRET-based zebrafish ERK reporter, Teen, and used quantitative FRET protocols to monitor non-physiological RASopathy-associated changes in ERK activation. In a multi-level experimental workflow, we tested the suitability of the Teen reporter to detect pan-embryo ERK activity correlates of morphometric alterations driven by the NS-causing Shp2D61G allele. RESULTS: Spectral unmixing- and acceptor photobleaching (AB)-FRET analyses captured pathological ERK activity preceding the manifestation of quantifiable body axes defects, a morphological pillar used to test the strength of SHP2 GoF mutations. Last, the work shows that by multi-modal FRET analysis, we can quantitatively trace back the modulation of ERK phosphorylation obtained by low-dose MEK inhibitor treatment to early development, before the onset of morphological defects. CONCLUSION: This work proves the usefulness of FRET imaging protocols on both live and fixed Teen ERK reporter fish to readily monitor and quantify pharmacologically- and genetically-induced ERK activity modulations in early embryos, representing a useful tool in pre-clinical applications targeting RAS-MAPK signaling.

Asunto(s)

Síndrome de Noonan , Pez Cebra , Animales , Humanos , Adolescente , Pez Cebra/genética , Pez Cebra/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Síndrome de Noonan/genética , Mutación , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo

RESUMEN

Mutations in BRAF are present in 4% of non-small cell lung cancer (NSCLC), of which half are well-characterized activating variants affecting codon 600 (classified as class I). These mutations, most commonly BRAF V600E, have been associated with response to BRAF/MEK-directed small molecule kinase inhibitors. NSCLC with kinase-activating BRAF mutations occurring at other codons (class II variants) represent a substantial portion of BRAF-mutated NSCLC, but use of targeted therapy in these tumors is still under investigation. Class II mutations have been described in other tumor types and have been associated with response to BRAF/MEK-targeted agents, although optimal treatment strategies for these patients are lacking. This report presents a case of a woman with metastatic NSCLC harboring a class II BRAF p.N486_P490del variant who had a sustained clinical response to combination therapy with dabrafenib and trametinib. This first report of the use of BRAF/MEK-targeted therapy for this variant in NSCLC supports consideration of such treatment for tumors with class II BRAF variants.

Asunto(s)

Carcinoma de Pulmón de Células no Pequeñas , Imidazoles , Neoplasias Pulmonares , Piridonas , Pirimidinonas , Femenino , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Proteínas Proto-Oncogénicas B-raf/genética , Oximas/uso terapéutico , Quinasas Quinasa Quinasa PAM , Mutación , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética

RESUMEN

BRAF mutations are found in 1-5% of non-small-cell lung cancer (NSCLC), with V600 and non-V600 accounting for approximately 50% each. It has been confirmed that targeted therapy with dabrafenib + trametinib is effective in patients with metastatic NSCLC carrying BRAF V600E mutations. Preclinical studies have shown that dabrafenib + trametinib may also have inhibitory effects on some types of non-V600E mutations, especially some class II BRAF mutations. However, the efficacy of dabrafenib + trametinib on non-V600E mutant NSCLC in clinical practice only exists in some case reports. Here, we report a case of NSCLC patient carrying BRAF ex15 p.T599dup, who showed a clinical response to the combined therapy of dabrafenib + trametinib.

Asunto(s)

Carcinoma de Pulmón de Células no Pequeñas , Imidazoles , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Proteínas Proto-Oncogénicas B-raf/genética , Oximas/uso terapéutico , Mutación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/uso terapéutico

RESUMEN

Brassinosteroids (BRs) are phytohormones that regulate stomatal development. In this study, we report that BR represses stomatal development in etiolated Arabidopsis (Arabidopsis thaliana) cotyledons via transcription factors BRASSINAZOLE RESISTANT 1 (BZR1) and bri1-EMS SUPPRESSOR1 (BES1), which directly target MITOGEN-ACTIVATED PROTEIN KINASE KINASE 9 (MKK9) and FAMA, 2 important genes for stomatal development. BZR1/BES1 bind MKK9 and FAMA promoters in vitro and in vivo, and mutation of the BZR1/BES1 binding motif in MKK9/FAMA promoters abolishes their transcription regulation by BZR1/BES1 in plants. Expression of a constitutively active MKK9 (MKK9DD) suppressed overproduction of stomata induced by BR deficiency, while expression of a constitutively inactive MKK9 (MKK9KR) induced high-density stomata in bzr1-1D. In addition, bzr-h, a sextuple mutant of the BZR1 family of proteins, produced overabundant stomata, and the dominant bzr1-1D and bes1-D mutants effectively suppressed the stomata-overproducing phenotype of brassinosteroid insensitive 1-116 (bri1-116) and brassinosteroid insensitive 2-1 (bin2-1). In conclusion, our results revealed important roles of BZR1/BES1 in stomatal development, and their transcriptional regulation of MKK9 and FAMA expression may contribute to BR-regulated stomatal development in etiolated Arabidopsis cotyledons.

Asunto(s)

Proteínas de Arabidopsis , Arabidopsis , Brasinoesteroides , Cotiledón , Proteínas de Unión al ADN , Regulación de la Expresión Génica de las Plantas , Proteínas Nucleares , Estomas de Plantas , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Brasinoesteroides/metabolismo , Estomas de Plantas/crecimiento & desarrollo , Estomas de Plantas/genética , Estomas de Plantas/efectos de los fármacos , Cotiledón/genética , Cotiledón/crecimiento & desarrollo , Cotiledón/metabolismo , Cotiledón/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Mutación/genética , Regiones Promotoras Genéticas/genética , Etiolado , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Unión Proteica/efectos de los fármacos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética

RESUMEN

OPINION STATEMENT: The integration of targeted therapy into the multimodal management of craniopharyngiomas represents a significant advancement in the field of neuro-oncology. Historically, the management of these tumors has been challenging due to their proximity to vital brain structures, necessitating a delicate balance between tumor control and the preservation of neurological function. Traditional treatment modalities, such as surgical resection and radiation, while effective, carry their own set of risks, including potential damage to surrounding healthy tissues and the potential for long-term side effects. Recent insights into the molecular biology of craniopharyngiomas, particularly the discovery of the BRAF V600E mutation in nearly all papillary craniopharyngiomas, have paved the way for a targeted systemic treatment approach. However, advances have been limited for adamantinomatous craniopharyngiomas. The success of BRAF/MEK inhibitors in clinical trials underscores the potential of these targeted therapies not only to control tumor growth but also to reduce the need for more invasive treatments, potentially minimizing treatment-related complications. However, the introduction of these novel therapies also brings forth new challenges, such as determining the optimal timing, sequencing, and duration of targeted treatments. Furthermore, there are open questions regarding which specific BRAF/MEK inhibitors to use, the potential need for combination therapy, and the strategies for managing intolerable adverse events. Finally, ensuring equitable access to these therapies, especially in healthcare systems with limited resources, is crucial to prevent widening healthcare disparities. In conclusion, targeted therapy with BRAF/MEK inhibitors holds great promise for improving outcomes and quality of life for patients with BRAF-mutated craniopharyngiomas. However, additional research is needed to address the questions that remain about its optimal use and integration into comprehensive treatment plans.

Asunto(s)

Craneofaringioma , Neoplasias Hipofisarias , Humanos , Craneofaringioma/diagnóstico , Craneofaringioma/genética , Craneofaringioma/terapia , Proteínas Proto-Oncogénicas B-raf/genética , Calidad de Vida , Neoplasias Hipofisarias/diagnóstico , Neoplasias Hipofisarias/terapia , Neoplasias Hipofisarias/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Mutación

RESUMEN

No prospective data were available prior to 2021 to inform selection between combination BRAF and MEK inhibition versus dual blockade of programmed cell death protein-1 (PD-1) and cytotoxic T lymphocyte antigen-4 (CTLA-4) as first-line treatment options for BRAFV600-mutant melanoma. SECOMBIT (NCT02631447) was a randomized, three-arm, noncomparative phase II trial in which patients were randomized to one of two sequences with immunotherapy or targeted therapy first, with a third arm in which an 8-week induction course of targeted therapy followed by a planned switch to immunotherapy was the first treatment. BRAF/MEK inhibitors were encorafenib plus binimetinib and checkpoint inhibitors ipilimumab plus nivolumab. Primary outcome of overall survival was previously reported, demonstrating improved survival with immunotherapy administered until progression and followed by BRAF/MEK inhibition. Here we report 4-year survival outcomes, confirming long-term benefit with first-line immunotherapy. We also describe preliminary results of predefined biomarkers analyses that identify a trend toward improved 4-year overall survival and total progression-free survival in patients with loss-of-function mutations affecting JAK or low baseline levels of serum interferon gamma (IFNy). These long-term survival outcomes confirm immunotherapy as the preferred first-line treatment approach for most patients with BRAFV600-mutant metastatic melanoma, and the biomarker analyses are hypothesis-generating for future investigations of predictors of durable benefit with dual checkpoint blockade and targeted therapy.

Asunto(s)

Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Proteínas Proto-Oncogénicas B-raf/genética , Ipilimumab/uso terapéutico , Inmunoterapia/métodos , Inhibidores de Proteínas Quinasas/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Neoplasias Cutáneas/genética , Mutación

RESUMEN

Osimertinib is a third-generation tyrosine kinase inhibitor clinically approved for first-line treatment of EGFR-mutant non-small cell lung cancer (NSCLC) patients. Although an impressive drug response is initially observed, in most of tumors, resistance occurs after different time and an alternative therapeutic strategy to induce regression disease is currently lacking. The hyperactivation of MEK/MAPKs, is one the most common event identified in osimertinib-resistant (OR) NSCLC cells. However, in response to selective drug pressure, the occurrence of multiple mechanisms of resistance may contribute to treatment failure. In particular, the epithelial-to-mesenchymal transition (EMT) and the impaired DNA damage repair (DDR) pathways are recognized as additional cause of resistance in NSCLC thus promoting tumor progression. Here we showed that concurrent upregulation of ITGB1 and DDR family proteins may be associated with an increase of EMT pathways and linked to both osimertinib and MEK inhibitor resistance to cell death. Furthermore, this study demonstrated the existence of an interplay between ITGB1 and DDR and highlighted, for the first time, that combined treatment of MEK inhibitor with DDRi may be relevant to downregulate ITGB1 levels and increase cell death in OR NSCLC cells.

Asunto(s)

Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Receptores ErbB/metabolismo , Resistencia a Antineoplásicos/genética , Mutación , Compuestos de Anilina/farmacología , Compuestos de Anilina/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Línea Celular Tumoral

RESUMEN

In June 2022, the FDA granted Accelerated Approval to the BRAF inhibitor dabrafenib in combination with the MEK inhibitor trametinib for the treatment of adult and paediatric patients (≥6 years of age) with unresectable or metastatic BRAFV600E-mutant solid tumours, except for BRAFV600E-mutant colorectal cancers. The histology-agnostic approval of dabrafenib plus trametinib marks the culmination of two decades of research into the landscape of BRAF mutations in human cancers, the biochemical mechanisms underlying BRAF-mediated tumorigenesis, and the clinical development of selective RAF and MEK inhibitors. Although the majority of patients with BRAFV600E-mutant tumours derive clinical benefit from BRAF inhibitor-based combinations, resistance to treatment develops in most. In this Review, we describe the biochemical basis for oncogenic BRAF-induced activation of MAPK signalling and pan-cancer and lineage-specific mechanisms of intrinsic, adaptive and acquired resistance to BRAF inhibitors. We also discuss novel RAF inhibitors and drug combinations designed to delay the emergence of treatment resistance and/or expand the population of patients with BRAF-mutant cancers who benefit from molecularly targeted therapies.

Asunto(s)

Neoplasias , Proteínas Proto-Oncogénicas B-raf , Adulto , Humanos , Niño , Proteínas Proto-Oncogénicas B-raf/genética , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/inducido químicamente , Imidazoles/uso terapéutico , Oximas/efectos adversos , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Mutación , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico

RESUMEN

RING finger 43 (RNF43), a RING-type E3 ubiquitin ligase, is a key regulator of WNT signaling and is mutated in 6-10% of pancreatic tumors. However, RNF43-mediated effects remain unclear, as only a few in vivo substrates of RNF43 are identified. Here, it is found that RNF43-mutated pancreatic cancer cells exhibit elevated B-RAF/MEK activity and are highly sensitive to MEK inhibitors. The depletion of RNF43 in normal pancreatic ductal cells also enhances MEK activation, suggesting that it is a physiologically regulated process. It is confirmed that RNF43 ubiquitinates B-RAF at K499 to promote proteasome-dependent degradation, resulting in reduced MEK activity and proliferative ability in cancer cells. In addition, phosphorylation of B-RAF at T491 suppresses B-RAF ubiquitination by decreasing the interaction between RNF43 and B-RAF. Mutations at K499 in B-RAF are identified in various cancer types. MEK and WNT inhibitors synergistically suppress the growth of RNF43-mutated pancreatic cancer cells in vitro and in vivo. Collectively, the research reveals a novel mechanism by which RNF43 inhibits B-RAF/MEK signaling to suppress tumor growth and provide a new strategy for the treatment of RNF43-inactivated pancreatic cancer.

Asunto(s)

Neoplasias Pancreáticas , Ubiquitina-Proteína Ligasas , Humanos , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación , Vía de Señalización Wnt/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo

RESUMEN

V-Raf murine sarcoma viral oncogene homolog B (BRAF) alteration is one of the most essential driver genes of non-small cell lung cancer (NSCLC). BRAF encodes serine/threonine protein kinases, and its mutations typically lead to protein compositional activation, thereby activating the mitogen-activated protein kinase kinase (MEK) signaling pathway. A promising new approach for the treatment of mutated BRAF and/or downstream MEK may provide customized treatment opportunities for BRAF driven NSCLC patients. However, combination therapy is necessary to overcome the difficulties such as short duration of benefit, poor therapeutic effect of non-V600 BRAF mutations and susceptibility to drug resistance. This article reviewed the progress in structural characteristics, related signaling pathways, mutation types of BRAF gene, and the clinical pathological relationship between BRAF mutations and NSCLC, as well as the therapy, in order to provide more evidences for clinical doctors to make treatment decisions.
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Asunto(s)

Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Animales , Ratones , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Proteínas Proto-Oncogénicas B-raf/genética , Mutación , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico

RESUMEN

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with poor prognosis. It is marked by extraordinary resistance to conventional therapies including chemotherapy and radiation, as well as to essentially all targeted therapies evaluated so far. More than 90% of PDAC cases harbor an activating KRAS mutation. As the most common KRAS variants in PDAC remain undruggable so far, it seemed promising to inhibit a downstream target in the MAPK pathway such as MEK1/2, but up to now preclinical and clinical evaluation of MEK inhibitors (MEKi) failed due to inherent and acquired resistance mechanisms. To gain insights into molecular changes during the formation of resistance to oncogenic MAPK pathway inhibition, we utilized short-term passaged primary tumor cells from ten PDACs of genetically engineered mice. We followed gain and loss of resistance upon MEKi exposure and withdrawal by longitudinal integrative analysis of whole genome sequencing, whole genome bisulfite sequencing, RNA-sequencing and mass spectrometry data. RESULTS: We found that resistant cell populations under increasing MEKi treatment evolved by the expansion of a single clone but were not a direct consequence of known resistance-conferring mutations. Rather, resistant cells showed adaptive DNA hypermethylation of 209 and hypomethylation of 8 genomic sites, most of which overlap with regulatory elements known to be active in murine PDAC cells. Both DNA methylation changes and MEKi resistance were transient and reversible upon drug withdrawal. Furthermore, MEKi resistance could be reversed by DNA methyltransferase inhibition with remarkable sensitivity exclusively in the resistant cells. CONCLUSION: Overall, the concept of acquired therapy resistance as a result of the expansion of a single cell clone with epigenetic plasticity sheds light on genetic, epigenetic and phenotypic patterns during evolvement of treatment resistance in a tumor with high adaptive capabilities and provides potential for reversion through epigenetic targeting.

Asunto(s)

Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animales , Ratones , Metilación de ADN , Proteínas Proto-Oncogénicas p21(ras)/genética , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , ADN/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/uso terapéutico , Línea Celular Tumoral , Mutación

RESUMEN

BACKGROUND: Ovarian cancer is one of the most common cancers in women. Profiles changes of microRNAs (miRNAs) are closely linked to malignant tumors. In the present study, we investigated expression of miR-451a in high-grade serous ovarian cancer (HGSOC). We also investigated the potential pathological roles and the likely mechanism of miR-451a in the development of HGSOC using animal models and cell lines. METHODS: Using bioinformatics techniques and a real-time PCR, we analyzed differently expressed miRNAs in HGSOC compared to normal tissue. MTT (i.e. 3-[4, 5-dimethyl thiazol-2-yl]-2,5-diphenyl tetrazolium bromide), EDU (i.e. 5-ethynyl-2'-deoxyuridine) and transwell assays were performed to investigate the effect of miR-451a on the proliferation and migration of HGSOC SKOV-3 cells. A dual luciferase reporter assay was performed to verify the targeting relationship of miR-451 and RAB5A (one of the Rab GTPase proteins that regulates endocytosis and vesicle transport). Also, we analyzed levels of the RAB5A mRNA and protein by real-time PCR, western blotting and immunohistochemistry assays in HGSOC cells and tissues. Finally, we performed in vivo experiments using HGSOC mice. RESULTS: miR-451a was substantially upregulated in HGSOC and associated with favorable clinical characteristics. miR-451a knockdown significantly increased growth and metastasis of HGSOC cell line SKOV-3 through Ras/Raf/mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling. In addition, RAB5A, an early endosome marker, was shown to be a direct target of miR-451a. Moreover, RAB5A is correlated with unfavorable clinical features and shows independent prognostic significance in HGSOC. CONCLUSIONS: We found that the miR-451a/RAB5A axis is associated with tumorigenesis and progression through the Ras/Raf/MEK/ERK pathway, providing prognostic indicators and therapeutic targets for patients with HGSOC.

Asunto(s)

MicroARNs , Neoplasias Ováricas , Proteínas de Unión al GTP rab5 , Animales , Femenino , Humanos , Ratones , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica , Sistema de Señalización de MAP Quinasas/genética , MicroARNs/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Neoplasias Ováricas/genética , Proteínas de Unión al GTP rab5/genética

RESUMEN

Ameloblastoma is a rare odontogenic tumor which may be complicated by hypercalcemia in advanced disease. Tumoral parathyroid hormone-related peptide (PTHrP) production and local osteolysis from paracrine factors have been proposed as mechanisms. Mitogen-activated protein kinase (MAPK) inhibitors have been successfully used in ameloblastomas with BRAF V600E mutation to reduce symptoms and decrease tumor burden. Serum calcium has been observed to normalize following treatment with MAPK inhibitors; however, the response of PTHrP and markers of bone turnover has not been reported. We describe a case of a 55-year-old female with PTHrP-mediated hypercalcemia secondary to BRAF V600E-positive ameloblastoma with pulmonary metastases. Following treatment with dabrafenib and trametinib, the patient experienced the regression of pulmonary lesions and normalization of serum calcium, PTHrP, and markers of bone turnover. Tissue samples of ameloblastoma carrying BRAF V600E mutation are more likely to express PTHrP than tissue samples carrying wild-type BRAF. In our case, resolution of PTHrP-mediated hypercalcemia following initiation of BRAF/MEK inhibition provides additional evidence that the MAPK pathway contributes to PTHrP synthesis. It also raises the question of whether MAPK inhibitors would be effective in treating PTHrP-mediated hypercalcemia associated with other malignancies harboring BRAF V600E mutation.

Asunto(s)

Ameloblastoma , Hipercalcemia , Femenino , Humanos , Persona de Mediana Edad , Proteína Relacionada con la Hormona Paratiroidea , Hipercalcemia/tratamiento farmacológico , Ameloblastoma/tratamiento farmacológico , Ameloblastoma/genética , Ameloblastoma/patología , Proteínas Proto-Oncogénicas B-raf/genética , Calcio , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Mutación

RESUMEN

BACKGROUND: Resistance to BRAF and MEK inhibitors in BRAF V600-mutant melanoma is common. Multiple resistance mechanisms involve heat-shock protein 90 (HSP90) clients, and a phase 1 study of vemurafenib with the HSP90 inhibitor XL888 in patients with advanced melanoma showed activity equivalent to that of BRAF and MEK inhibitors. METHODS: Vemurafenib (960 mg orally twice daily) and cobimetinib (60 mg orally once daily for 21 of 28 days) with escalating dose cohorts of XL888 (30, 45, 60, or 90 mg orally twice weekly) was investigated in a phase 1 trial of advanced melanoma, with a modified Ji dose-escalation design. RESULTS: Twenty-five patients were enrolled. After two dose-limiting toxicities (DLTs) (rash and acute kidney injury) in the first cohort, lower doses of vemurafenib (720 mg) and cobimetinib (40 mg) were investigated with the same XL888 doses. Three DLTs (rash) were observed in 12 patients in the XL888 60-mg cohort, and this was determined as the maximum tolerated dose. Objective responses were observed in 19 patients (76%), and the median progression-free survival was 7.6 months, with a 5-year progression-free survival rate of 20%. The median overall survival was 41.7 months, with a 5-year overall survival rate of 37%. Single-cell RNA sequencing was performed on baseline and on-treatment biopsies; treatment was associated with increased immune cell influx (CD4-positive and CD8-positive T cells) and decreased melanoma cells. CONCLUSIONS: Combined vemurafenib and cobimetinib plus XL888 had significant toxicity, requiring frequent dose reductions, which may have contributed to the relatively low progression-free survival despite a high tumor response rate. Given overlapping toxicities, caution must be used when combining HSP90 inhibitors with BRAF and MEK inhibitors.

Asunto(s)

Exantema , Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/patología , Vemurafenib , Proteínas Proto-Oncogénicas B-raf , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Inhibidores de Proteínas Quinasas/efectos adversos , Exantema/inducido químicamente , Exantema/tratamiento farmacológico , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/uso terapéutico , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Mutación , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología