Unlabelled: We have previously shown that the microenvironment of human embryonic stem cells (hESCs) is able to change and reprogram aggressive cancer cells to a less aggressive state. Some mechanisms implicated in the phenotypic changes observed after this exposure are mainly associated with the Nodal signaling pathway, which plays a key role in tumor cell plasticity. However, several other molecular mechanisms might be related directly and/or indirectly to these changes, including microRNA (miRNA) regulation and DNA methylation.

Aim: To further explore the epigenetic mechanisms potentially underlying the phenotypic changes that occur after exposing metastatic melanoma cells to a hESC microenvironment.

Materials & Methods: A total of 365 miRNAs were screened using the TaqMan® Low Density Arrays. We also evaluated whether DNA methylation could be one of the factors regulating the expression of the inhibitor of Nodal, Lefty, in hESCs (where it is highly expressed) vs melanoma cells (where it is not expressed).

Results: Using these experimental approaches, we identified miRNAs that are up- and down-regulated in melanoma cells exposed to a hESC microenvironment, such as miR-302a and miR-27b, respectively. We also demonstrate that Notch4 is one of the targets of miR-302a, which is upstream of Nodal. Additionally, one of the mechanisms that might explain the absence of the inhibitor of Nodal, Lefty, in cancer cells is silencing by DNA methylation, which provides new insights into the unregulated expression of Nodal in melanoma.

Conclusion: These findings suggest that epigenetic changes such as DNA methylation and regulation by microRNAs might play a significant role in tumor cell plasticity and the metastatic phenotype.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2872497PMC
http://dx.doi.org/10.2217/epi.09.25DOI Listing

Publication Analysis

Top Keywords

melanoma cells
12
dna methylation
12
cancer cells
8
phenotypic changes
8
role tumor
8
tumor cell
8
cell plasticity
8
inhibitor nodal
8
nodal lefty
8
cells
7

Similar Publications

Extracellular vesicles (EVs) are generated in all cells. Systemic administration of allogenic EVs derived from epithelial and mesenchymal cells has been shown to be safe, despite carrying an array of functional molecules, including thousands of proteins. To address whether epithelial cell-derived EVs can be modified to acquire the capacity to induce an immune response, we engineered 293T EVs to harbor the immunomodulatory molecules CD80, OX40L, and PD-L1.

View Article and Find Full Text PDF

Purpose Of Review: Recent research underscores the significant influence of the skin and gut microbiota on melanoma and nonmelanoma skin cancer (NMSC) development and treatment outcomes. This review aims to synthesize current findings on how microbiota modulates immune responses, particularly enhancing the efficacy of immunotherapies such as immune checkpoint inhibitors (ICIs).

Recent Findings: The microbiota's impact on skin cancer is multifaceted, involving immune modulation, inflammation, and metabolic interactions.

View Article and Find Full Text PDF

Melanoma, a highly aggressive skin cancer, poses significant challenges due to its rapid metastases and high mortality rates. While metformin (Met), a first-line medication for type 2 diabetes, has shown promise in inhibiting tumor growth and metastases, its clinical efficacy in cancer therapy is limited by low bioavailability, short half-life, and gastrointestinal adverse reactions associated with oral administration. In this study, we developed a hollow mesoporous polydopamine nanocomposite (HMPDA-PEG@Met@AB) coloaded with Met and ammonia borane (AB), designed to enable a combined gas-assisted, photothermal, and chemotherapeutic approach for melanoma treatment.

View Article and Find Full Text PDF

Endogenous retroviral (ERV) RNA is highly expressed in cancer, although the molecular causes and consequences remain unknown. We found that ZC3H18 (Z18), a component of multiple nuclear RNA surveillance complexes, has recurrent truncating mutations in cancer. We show that Z18 mutations are oncogenic and that Z18 plays an evolutionarily conserved role in nuclear RNA surveillance of ERV RNA.

View Article and Find Full Text PDF

In cutaneous melanoma, epigenetic dysregulation is implicated in drug resistance and tumor immune escape. However, the epigenetic mechanisms that influence immune escape remain poorly understood. To elucidate how epigenetic dysregulation alters the expression of surface proteins that may be involved in drug targeting and immune escape, we performed a 3-dimensional surfaceome screen in primary melanoma cultures and identified the DNA-methyltransferase inhibitor decitabine as significantly upregulating the costimulatory molecule ICAM-1.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!