lncRNAs-EZH2 interaction as promising therapeutic target in cutaneous melanoma

LncRNAs and IgA nephropathy: underlying molecular pathways and clinical applications

IgA nephropathy (IgAN), also known as Berger's disease, is a prevalent kidney disorder caused by the accumulation of IgA antibodies in the glomerular tissue. Long noncoding RNAs (lncRNAs), a class of noncoding RNAs longer than 200 nucleotides, play crucial roles in regulating various cellular and molecular processes, including translation, chromatin remodeling, and transcriptional efficiency. Research has highlighted the significant impact of lncRNA imbalances on the development and progression of kidney diseases, including IgAN. These molecules influence several key signaling pathways, such as PI3K/AKT/mTOR, PTEN, Notch, JNK, and immune-related pathways, with their dysregulation contributing to IgAN pathogenesis. This review aims to provide a comprehensive analysis of the molecular signaling pathways involving lncRNAs in IgAN, underscoring their potential as biomarkers for screening, diagnosis, and prevention. Furthermore, it explores the therapeutic potential of lncRNAs as precise targets for personalized treatment strategies.

Relapse-free survival in a pediatric patient with recurrent EZH2-mutant melanoma treated with adjuvant tazemetostat

Enhancer of zeste homolog 2 (EZH2) is an essential epigenetic regulator of H3K27 histone methylation and is mutated or overexpressed in a wide variety of cancers. In melanoma, EZH2 overexpression contributes to excessive trimethylation of H3K27 on tumor suppressor genes and has been proposed to be a mechanism of tumor progression and metastasis. EZH2-targeted therapies have been successfully used to treat patients with follicular lymphoma and epithelioid sarcoma, but their clinical use in melanoma has not been described. Here, we describe a pediatric patient with multiply relapsed melanoma harboring an EZH2 A692V missense mutation, treated adjuvantly with the EZH2 inhibitor tazemetostat, who experienced a prolonged relapse-free survival.

Exploring oncogenic roles and clinical significance of EZH2: focus on non-canonical activities

The enhancer of zeste homolog 2 (EZH2) is a catalytic component of Polycomb repressive complex 2 (PRC2) mediating the methylation of histone 3 lysine 27 (H3K27me3) and hence the epigenetic repression of target genes, known as canonical function. Growing evidence indicates that EZH2 has non-canonical roles that are exerted as PRC2-dependent and PRC2-independent methylation of non-histone proteins, and methyltransferase-independent interactions of EZH2 with various proteins contributing to gene expression regulation and alterations in the protein stability. EZH2 is frequently mutated and/or its expression is deregulated in various cancer types. The cancer sensitivity to inhibitors of EZH2 enzymatic activity and state-of-the-art approaches to deplete EZH2 with chemical degraders are discussed. This review also presents the clinical trials in various phases that evaluate the use of EZH2 inhibitors, both as monotherapy and in combination with other agents for the treatment of patients with diverse types of cancers.

Corynoxine exerts the anti-tumor effect on esophageal squamous cell carcinoma principally via the EZH2-DUSP5-ERK1/2-mediated cell growth inhibition

BACKGROUND

Esophageal cancer is one of the most prevalent malignant tumors and the sixth largest cause of tumor-associated death worldwide. Squamous cell carcinoma (ESCC) accounts for 85 % of all esophageal cancer cases. ESCC treatment remains to be significantly difficult. Corynoxine (Cory) is a tetracyclic hydroxyindole alkaloid isolated from Uncaria macrophylla. It is unclear whether Cory has an anti-tumor effect on ESCC.

PURPOSE

To determine the anti-tumor activity of Cory and the associated mechanisms in ESCC.

STUDY DESIGN

Cory's effects on proliferation, apoptosis, migration, and invasion, as well as the underlying molecular causes were assessed using two ESCC cell lines, KYSE150 and TE-1. A xenograft mouse model was then applied to evaluate the anti-tumor activity of Cory in vivo.

METHODS

Western blot, assays including CCK-8, colony formation, EdU staining, TUNEL staining, cell scratch and Transwell, and a xenograft mouse model were used in this study.

RESULTS

Cory suppressed cell growth, provoked cell apoptosis, and hindered cell migration and invasion of ESCC cells. DUSP5 knockdown reduced the Cory-induced cell death and restored cell migration and invasion through ERK1/2 activation. Further analyses showed that Cory promoted DUSP5 expression via inhibiting EZH2 expression, leading to inactivation of ERK1/2 signaling and the subsequent cell growth inhibition of ESCC. In vivo experiments disclosed that Cory suppressed tumor growth of ESCC through upregulating DUSP5 expression.

CONCLUSIONS

Cory plays an anti-tumor role in ESCC by regulating EZH2-DUSP5-ERK1/2 signaling pathway. Cory may be promising to be a novel therapy for treating ESCC.

Advances in Melanoma: From Genetic Insights to Therapeutic Innovations

Advances in melanoma research have unveiled critical insights into its genetic and molecular landscape, leading to significant therapeutic innovations. This review explores the intricate interplay between genetic alterations, such as mutations in BRAF, NRAS, and KIT, and melanoma pathogenesis. The MAPK and PI3K/Akt/mTOR signaling pathways are highlighted for their roles in tumor growth and resistance mechanisms. Additionally, this review delves into the impact of epigenetic modifications, including DNA methylation and histone changes, on melanoma progression. The tumor microenvironment, characterized by immune cells, stromal cells, and soluble factors, plays a pivotal role in modulating tumor behavior and treatment responses. Emerging technologies like single-cell sequencing, CRISPR-Cas9, and AI-driven diagnostics are transforming melanoma research, offering precise and personalized approaches to treatment. Immunotherapy, particularly immune checkpoint inhibitors and personalized mRNA vaccines, has revolutionized melanoma therapy by enhancing the body's immune response. Despite these advances, resistance mechanisms remain a challenge, underscoring the need for combined therapies and ongoing research to achieve durable therapeutic responses. This comprehensive overview aims to highlight the current state of melanoma research and the transformative impacts of these advancements on clinical practice.

Regulatory RNAs: role as scaffolds assembling protein complexes and their epigenetic deregulation

Recently, new data have been added to the interaction between non-coding RNAs (ncRNAs) and epigenetic machinery. Epigenetics includes enzymes involved in DNA methylation, histone modifications, and RNA modifications, and mechanisms underlying chromatin structure, repressive states, and active states operating in transcription. The main focus is on long ncRNAs (lncRNAs) acting as scaffolds to assemble protein complexes. This review does not cover RNA's role in sponging microRNAs, or decoy functions. Several lncRNAs were shown to regulate chromatin activation and repression by interacting with Polycomb repressive complexes and mixed-lineage leukemia (MLL) activating complexes. Various groups reported on enhancer of zeste homolog 2 (EZH2) interactions with regulatory RNAs. Knowledge of the function of these complexes opens the perspective to develop new therapeutics for cancer treatment. Lastly, the interplay between lncRNAs and epitranscriptomic modifications in cancers paves the way for new targets in cancer therapy. The approach to inhibit lncRNAs interaction with protein complexes and perspective to regulate epitrascriptomics-regulated RNAs may bring new compounds as therapeuticals in various types of cancer.

RPTOR mutation: a novel predictor of efficacious immunotherapy in melanoma

Identifying biomarkers to evaluate the therapeutic effect of immune checkpoint inhibitors (ICIs) is crucial. Regulatory Associated Protein of MTOR Complex 1 (RPTOR), one of the genes in the mTOR pathway, plays a role in regulating tumor progression. However, the connection between RPTOR mutation and the efficacy of ICIs in melanoma remains unclear. The data of ICIs-treated melanoma patients in discovery (n = 384) and validation (n = 320) cohorts were obtained from cBioPortal databases. The genomic data in the two cohorts was used to investigate the connection between RPTOR mutation and immunotherapy efficacy. The underlying mechanisms were explored based on data from the The Cancer Genome Atlas (TCGA)-skin cutaneous melanoma (SKCM) cohort. Compared to melanoma patients with RPTOR wildtype (RPTOR-WT), RPTOR-mutation (RPTOR-Mut) patients achieved prolonged overall survival (OS) in both discovery cohort (median OS of 49.3 months vs. 21.7 months; HR = 0.41, 95% CI: 0.18-0.92; P = 0.026) and validation cohorts (not reached vs. 42.0 months; HR = 0.34, 95% CI: 0.11-1.06; P = 0.049). RPTOR-Mut melanoma patients exhibited a higher objective response rate (ORR) than RPTOR-WT patients in the discovery cohort (55.0% vs. 29.0%, P = 0.022). RPTOR-Mut patients exhibited higher TMB than RPTOR-WT patients in both discovery and validation cohorts (P < 0.001). RPTOR-Mut melanoma patients had an increased number of DNA damage response (DDR) mutations in TCGA-SKCM cohort. Immune cell infiltration analysis suggested that activated CD4 memory T cells were more enriched in RPTOR-Mut tumors. RPTOR-Mut melanoma patients had higher expression levels of immune-related genes than the RPTOR-WT patients. Our results suggest that RPTOR mutation could serve as a predictor of effective immunotherapy for melanoma.