Identification of metastasis-suppressive microRNAs in primary melanoma

Non-coding RNAs in BRAF-mutant melanoma: targets, indicators, and therapeutic potential

Melanoma, a highly aggressive skin cancer, is often driven by BRAF mutations, such as the V600E mutation, which promotes cancer growth through the MAPK pathway and contributes to treatment resistance. Understanding the role of non-coding RNAs (ncRNAs) in these processes is crucial for developing new therapeutic strategies. This review aims to elucidate the relationship between ncRNAs and BRAF mutations in melanoma, focusing on their regulatory roles and impact on treatment resistance. We comprehensively reviewed current literature to synthesize evidence on ncRNA-mediated regulation of BRAF-mutant melanoma and their influence on therapeutic responses. Key ncRNAs, including microRNAs and long ncRNAs, were identified as significant regulators of melanoma development and therapy resistance. MicroRNAs such as miR-15/16 and miR-200 families modulate critical pathways like Wnt signaling and melanogenesis. Long ncRNAs like ANRIL and SAMMSON play roles in cell growth, invasion, and drug susceptibility. Specific ncRNAs, such as BANCR and RMEL3, intersect with the MAPK pathway, highlighting their potential as therapeutic targets or biomarkers in BRAF-mutant melanoma. Additionally, ncRNAs involved in drug resistance, such as miR-579-3p and miR-1246, target processes like autophagy and immune checkpoint regulation. This review highlights the pivotal roles of ncRNAs in regulating BRAF-mutant melanoma and their contribution to drug resistance. These findings underscore the potential of ncRNAs as biomarkers and therapeutic targets, paving the way for innovative treatments to improve outcomes for melanoma patients.

MicroRNA expression alteration in chronic thromboembolic pulmonary hypertension: A systematic review

Chronic thromboembolic pulmonary hypertension (CTEPH) is marked by persistent blood clots in pulmonary arteries, leading to significant morbidity and mortality. Emerging evidence highlights the role of microRNAs (miRNAs) in pulmonary hypertension, though findings on miRNA expression in CTEPH remain limited and inconsistent. This systematic review evaluates miRNA expression changes in CTEPH and their direction. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we registered our protocol in International Prospective Register of Systematic Reviews (CRD42024524469). We included studies on miRNA expression in CTEPH with comparative or analytical designs, excluding nonhuman studies, interventions, non-English texts, conference abstracts, and editorials. Databases searched included PubMed, EMBASE, Scopus, CENTRAL, and ProQuest. The Quality Assessment of Diagnostic Accuracy Studies-2 tool assessed bias risk, and results were synthesized narratively. Of 313 unique studies, 39 full texts were reviewed, and 9 met inclusion criteria, totaling 235 participants. Blood samples were analysed using quantitative real time polymerase chain reaction. Seven miRNAs (miR-665, miR-3202, miR-382, miR-127, miR-664, miR-376c, miR-30) were uniformly upregulated, while nine (miR-20a-5p13, miR-17-5p, miR-93-5p, miR-22, let-7b, miR-106b-5p, miR-3148, miR-320-a, miR-320b) were downregulated in CTEPH patients. Two upregulated miRNAs (miR-127 and miR-30a) were consistently associated with previous evidence in the mechanism inducing the development of CTEPH, and five downregulated miRNAs (miR-20-a, miR-17-5p, miR-93-5p, let-7b, miR-106b-5p) were associated with a protective effect against CTEPH. We also identified gaps in the literature where the evidence for five upregulated miRNAs (miR-665, miR-3202, miR-382, miR-664 and miR-376c) and four downregulated miRNAs (miR-22, miR-3148, miR-320-a, and miR-320b) in CTEPH is conflicting. Our findings offer insights into the role of miRNAs in CTEPH and underscore the need for further research to validate these miRNAs as biomarkers or therapeutic targets.

Association of miR-146a-5p and miR-21-5p with Prognostic Features in Melanomas

BACKGROUND

Cutaneous melanoma (CM) is one of the most lethal tumors among skin cancers and its incidence is rising worldwide. Recent data support the role of microRNAs (miRNAs) in melanoma carcinogenesis and their potential use as disease biomarkers.

METHODS

We quantified the expression of miR-146a-5p and miR-21-5p in 170 formalin-fixed paraffin embedded (FFPE) samples of CM, namely 116 superficial spreading melanoma (SSM), 26 nodular melanoma (NM), and 28 lentigo maligna melanoma (LMM). We correlated miRNA expression with specific histopathologic features including Breslow thickness (BT), histological subtype, ulceration and regression status, and mitotic index.

RESULTS

miR-146a-5p and miR-21-5p were significantly higher in NM compared to SSM and LMM. The positive correlation between miR-146a-5p and miR-21-5p expression and BT was confirmed for both miRNAs in SSM. Considering the ulceration status, we assessed that individual miR-21-5p expression was significantly higher in ulcerated CMs. The increased combined expression of the two miRNAs was strongly associated with ulceration (p = 0.0093) and higher mitotic rate (≥1/mm2) (p = 0.0005). We demonstrated that the combination of two-miRNA expression and prognostic features (BT and ulceration) can better differentiate cutaneous melanoma prognostic groups, considering overall survival and time-to-relapse clinical outcomes. Specifically, miRNA expression can further stratify prognostic groups among patients with BT ≥ 0.8 mm but without ulceration. Our findings provide further insights into the characterization of CM with specific prognostic features. The graphical abstract was created with BioRender.com.

Analysis of Genes Related to Invadopodia Formation and CTTN in Oral Squamous Cell Carcinoma-A Systematic Gene Expression Analysis

Successful treatment for any type of carcinoma largely depends on understanding the patterns of invasion and migration. For oral squamous cell carcinoma (OSCC), these processes are not entirely understood as of now. Invadopodia and podosomes, called invadosomes, play an important role in cancer cell invasion and migration. Previous research has established that cortactin (CTTN) is a major inducer of invadosome formation. However, less is known about the expression patterns of CTTN and other genes related to it or invadopodia formation in OSCC during tumor progression in particular. In this study, gene expression patterns of CTTN and various genes (n = 36) associated with invadopodia formation were analyzed to reveal relevant expression patterns and give a comprehensive overview of them. The genes were analyzed from a whole genome dataset of 83 OSCC samples relating to tumor size, grading, lymph node status, and UICC (Union for Internatioanl Cancer Control). The data revealed significant overexpression of 18 genes, most notably CTTN, SRC (SRC proto-onocogene, non-receptor tyrosine kinase), EGFR (epidermal growth factor receptor), SYK (spleen associated tyrosine kinase), WASL (WASP like actin nucleation promotion factor), and ARPC2 (arrestin beta 1) due to their significant correlation with further tumor parameters. This study is one of the first to summarize the expression patterns of CTTN and related genes in a complex group of OSCC samples.

In Vivo miRNA Decoy Screen Reveals miR-124a as a Suppressor of Melanoma Metastasis

Melanoma is a highly prevalent cancer with an increasing incidence worldwide and high metastatic potential. Brain metastasis is a major complication of the disease, as more than 50% of metastatic melanoma patients eventually develop intracranial disease. MicroRNAs (miRNAs) have been found to play an important role in the tumorigenicity of different cancers and have potential as markers of disease outcome. Identification of relevant miRNAs has generally stemmed from miRNA profiling studies of cells or tissues, but these approaches may have missed miRNAs with relevant functions that are expressed in subfractions of cancer cells. We performed an unbiased in vivo screen to identify miRNAs with potential functions as metastasis suppressors using a lentiviral library of miRNA decoys. Notably, we found that a significant fraction of melanomas that metastasized to the brain carried a decoy for miR-124a, a miRNA that is highly expressed in the brain/neurons. Additional loss- and gain-of-function in vivo validation studies confirmed miR-124a as a suppressor of melanoma metastasis and particularly of brain metastasis. miR-124a overexpression did not inhibit tumor growth in vivo, underscoring that miR-124a specifically controls processes required for melanoma metastatic growth, such as seeding and growth post-extravasation. Finally, we provide proof of principle of this miRNA as a promising therapeutic agent by showing its ability to impair metastatic growth of melanoma cells seeded in distal organs. Our efforts shed light on miR-124a as an antimetastatic agent, which could be leveraged therapeutically to impair metastatic growth and improve patient survival.

miRNA-guided reprogramming of glucose and glutamine metabolism and its impact on cell adhesion/migration during solid tumor progression

MicroRNAs (miRNAs) are small, non-coding RNAs about 22 nucleotides in length that regulate the expression of target genes post-transcriptionally, and are highly involved in cancer progression. They are able to impact a variety of cell processes such as proliferation, apoptosis and differentiation and can consequently control tumor initiation, tumor progression and metastasis formation. miRNAs can regulate, at the same time, metabolic gene expression which, in turn, influences relevant traits of malignancy such as cell adhesion, migration and invasion. Since the interaction between metabolism and adhesion or cell movement has not, to date, been well understood, in this review, we will specifically focus on miRNA alterations that can interfere with some metabolic processes leading to the modulation of cancer cell movement. In addition, we will analyze the signaling pathways connecting metabolism and adhesion/migration, alterations that often affect cancer cell dissemination and metastasis formation.

Signal pathways of melanoma and targeted therapy

Melanoma is the most lethal skin cancer that originates from the malignant transformation of melanocytes. Although melanoma has long been regarded as a cancerous malignancy with few therapeutic options, increased biological understanding and unprecedented innovations in therapies targeting mutated driver genes and immune checkpoints have substantially improved the prognosis of patients. However, the low response rate and inevitable occurrence of resistance to currently available targeted therapies have posed the obstacle in the path of melanoma management to obtain further amelioration. Therefore, it is necessary to understand the mechanisms underlying melanoma pathogenesis more comprehensively, which might lead to more substantial progress in therapeutic approaches and expand clinical options for melanoma therapy. In this review, we firstly make a brief introduction to melanoma epidemiology, clinical subtypes, risk factors, and current therapies. Then, the signal pathways orchestrating melanoma pathogenesis, including genetic mutations, key transcriptional regulators, epigenetic dysregulations, metabolic reprogramming, crucial metastasis-related signals, tumor-promoting inflammatory pathways, and pro-angiogenic factors, have been systemically reviewed and discussed. Subsequently, we outline current progresses in therapies targeting mutated driver genes and immune checkpoints, as well as the mechanisms underlying the treatment resistance. Finally, the prospects and challenges in the development of melanoma therapy, especially immunotherapy and related ongoing clinical trials, are summarized and discussed.

Non-coding RNAs in melanoma: Biological functions and potential clinical applications

Malignant melanoma (MM) is a malignant tumor that originates from melanocytes and has a high mortality rate. Therefore, early diagnosis and treatment are very important for survival. So far, the exact molecular mechanism leading to the occurrence of melanoma, especially the molecular metastatic mechanism, remains largely unknown. Non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNA (circRNAs), have been investigated and found to play vital roles in regulating tumor occurrence and development, including melanoma. In this review, we summarize the progress of recent research on the effects of ncRNAs on melanoma and attempt to elucidate the role of ncRNAs as molecular markers or potential targets that will provide promising application perspectives on melanoma.

Heterogeneity of Melanoma Cell Responses to Sleep Apnea-Derived Plasma Exosomes and to Intermittent Hypoxia

Obstructive sleep apnea (OSA) is associated with increased cutaneous melanoma incidence and adverse outcomes. Exosomes are secreted by most cells, and play a role in OSA-associated tumor progression and metastasis. We aimed to study the effects of plasma exosomes from OSA patients before and after adherent treatment with continuous positive airway pressure (CPAP) on melanoma cells lines, and also to identify exosomal miRNAs from melanoma cells exposed to intermittent hypoxia (IH) or normoxia. Plasma-derived exosomes were isolated from moderate-to-severe OSA patients before (V1) and after (V2) adherent CPAP treatment for one year. Exosomes were co-incubated with three3 different melanoma cell lines (CRL 1424; CRL 1619; CRL 1675) that are characterized by genotypes involving different mutations in BRAF, STK11, CDKN2A, and PTEN genes to assess the effect of exosomes on cell proliferation and migration, as well as on pAMK activity in the presence or absence of a chemical activator. Subsequently, CRL-1424 and CRL-1675 cells were exposed to intermittent hypoxia (IH) and normoxia, and exosomal miRNAs were identified followed by GO and KEG pathways and gene networks. The exosomes from these IH-exposed melanoma cells were also administered to THP1 macrophages to examine changes in M1 and M2 polarity markers. Plasma exosomes from V1 increased CRL-1424 melanoma cell proliferation and migration compared to V2, but not the other two cell lines. Exposure to CRL-1424 exosomes reduced pAMPK/tAMPK in V1 compared to V2, and treatment with AMPK activator reversed the effects. Unique exosomal miRNAs profiles were identified for CRL-1424 and CRL-1675 in IH compared to normoxia, with six miRNAs being regulated and several KEGG pathways were identified. Two M1 markers (CXCL10 and IL6) were significantly increased in monocytes when treated with exosomes from IH-exposed CRL-1424 and CRL-1625 cells. Our findings suggest that exosomes from untreated OSA patients increase CRL-1424 melanoma malignant properties, an effect that is not observed in two other melanoma cell lines. Exosomal cargo from CRL-1424 cells showed a unique miRNA signature compared to CRL-1675 cells after IH exposures, suggesting that melanoma cells are differentially susceptible to IH, even if they retain similar effects on immune cell polarity. It is postulated that mutations in STK-11 gene encoding for the serine/threonine kinase family that acts as a tumor suppressor may underlie susceptibility to IH-induced metabolic dysfunction, as illustrated by CRL-1424 cells.

Upregulated circRAD18 promotes tumor progression by reprogramming glucose metabolism in papillary thyroid cancer

Background

By regulating complex functional processes, circRNAs are crucial in the development of different cancers. Nevertheless, most circRNAs in papillary thyroid cancer metabolic reprogramming remain unknown.

Methods

The expression of circRNA was assessed by qRT-PCR in papillary thyroid cancer tissues and cell lines. Cell proliferation and glucose intake experiments were performed by certain kit. Transwell assays and wound healing assays were performed to investigate the function of circRNA in metastasis. In addition, a serious of molecular experiments were conducted to determine the exact mechanism of circRAD18. Luciferase reporter and RNA immunoprecipitation assay were conducted to determine the molecular interaction between circRNA and miRNA.

Results

We characterized circRAD18 as a significantly upregulated circRNA in papillary thyroid tissues and cell lines and found its downregulation could inhibit the growth and metastasis ability of papillary thyroid cancer. Interestingly, we found that circRAD18 was involved in glucose metabolism reprogramming of papillary thyroid cancer, and its silence could remarkably inhibit cell glucose uptake and lactate production in papillary thyroid cancer cells. Inhibition of circRAD18 could decrease the expression level of PDK1 protein by sponging miR-516b.

Conclusions

This study verified the novel function of the circRAD18-miR-516b-PDK1 axis in papillary thyroid cancer metabolic reprogramming progression, which has potential to be a novel therapeutic target.

Micro RNAs Promoting Growth and Metastasis in Preclinical In Vivo Models of Subcutaneous Melanoma

During the last years a considerable therapeutic progress in melanoma patients with the RAF V600E mutation via RAF/MEK pathway inhibition and immuno-therapeutic modalities has been witnessed. However, the majority of patients relapse after therapy. Therefore, a deeper understanding of the pathways driving oncogenicity and metastasis of melanoma is of paramount importance. In this review, we summarize microRNAs modulating tumor growth, metastasis, or both, in preclinical melanoma-related in vivo models and possible clinical impact in melanoma patients as modalities and targets for treatment of melanoma. We have identified miR-199a (ApoE, DNAJ4), miR-7-5p (RelA), miR-98a (IL6), miR-219-5p (BCL2) and miR-365 (NRP1) as possible targets to be scrutinized in further target validation studies.

MicroRNA Signature in Melanoma: Biomarkers and Therapeutic Targets

Melanoma is the utmost fatal kind of skin neoplasms. Molecular changes occurring during the pathogenic processes of initiation and progression of melanoma are diverse and include activating mutations in BRAF and NRAS genes, hyper-activation of PI3K/AKT pathway, inactivation of p53 and alterations in CDK4/CDKN2A axis. Moreover, several miRNAs have been identified to be implicated in the biology of melanoma through modulation of expression of genes being involved in these pathways. In the current review, we provide a summary of the bulk of information about the role of miRNAs in the pathobiology of melanoma, their possible application as biomarkers and their emerging role as therapeutic targets for this kind of skin cancer.

Aberrant Chloride Intracellular Channel 4 Expression Is Associated With Adverse Outcome in Cytogenetically Normal Acute Myeloid Leukemia

Background and Methods: Acute myeloid leukemia (AML), which starts in the bone marrow, is a group of hematopoietic stem cell disorders. Chloride intracellular channel 4 (CLIC4) is regulated by p53, c-Myc, and TGF-β. It induces the NF-κB-dependent activation of HIF (hypoxia-inducible factor) and participates in tumor growth through its microenvironmental function. However, its prognostic value in AML remains unclear, as well as its co-expression biomarkers. In this study, we evaluated the prognostic significance of CLIC4 expression using two independent large cohorts of cytogenetically normal AML (CN-AML) patients. Multivariable analysis and multi-omics analysis with weighted correlation network analysis (WGCNA) in the CN-AML group were also presented. Based on CLIC4 and its related genes, microRNA-target gene interaction network analysis and downstream gene ontology analysis were performed to unveil the complex functions behind CLIC4. Results: We demonstrated that the overexpression of CLIC4 was notably associated with unfavorable outcome in the two independent cohorts of CN-AML patients [overall survival (OS) and event-free survival (EFS): P < 0.0001, n = 185; OS: P = 0.016, n = 232], as well as in the European LeukemiaNet (ELN) Intermediate-I group (OS: P = 0.015, EFS: P = 0.012, n = 115), the National Comprehensive Cancer Network Intermediate Risk AML group (OS and EFS: P < 0.0001, n = 225), and the non-M3 AML group (OS and EFS: P < 0.0001, n = 435). Multivariable analysis further validated CLIC4 as a high-risk factor in the CN-AML group. Multi-omics analysis presented the overexpression of CLIC4 as associated with the co-expression of the different gene sets in leukemia, up/downregulation of the immune-related pathways, dysregulation of microRNAs, and hypermethylation around the CpG islands, in open sea regions, and in different gene structural fragments including TSS1500, gene body, 5'UTR region, 3'UTR region, and the first exon. By further performing WGCNA on multi-omics data, certain biomarkers that are co-expressed with CLIC4 were also unveiled. Conclusion: We demonstrated that CLIC4 is a novel, potential unfavorable prognosticator and therapeutic target for CN-AML. As having a key role in CN-AML, the interactions between CLIC4 and other genomics and transcriptomics data were confirmed by performing microRNA-target gene interaction network analysis and gene ontology enrichment analysis. The experimental result provides evidence for the clinical strategy selection of CN-AML patients.

Circ_0079593 facilitates proliferation, metastasis, glucose metabolism and inhibits apoptosis in melanoma by regulating the miR-516b/GRM3 axis

Many studies confirm that circular RNA (circRNA) plays an important regulatory role in the malignant progression of cancer, including melanoma. However, the role of a novel circRNA, circ_0079593, in melanoma is unclear. The expression levels of circ_0079593 and miR-516b were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was measured by cell counting kit-8 (CCK-8) assay, and cell migration and invasion were evaluated using transwell assay. Meanwhile, western blot (WB) analysis was employed to determine the levels of proliferation and metastasis-related proteins, as well as metabotropic glutamate receptor 3 (GRM3) protein. Furthermore, cell apoptosis was tested by detecting the cell apoptosis rate and Caspase-3 activity. The glucose consumption and lactate production of cells were measured to evaluate cell glucose metabolism. Moreover, dual-luciferase reporter assay and biotin-labeled RNA pull-down assay were used to confirm the interaction between miR-516b and circ_0079593 or GRM3. In addition, mice xenograft models were constructed to explore the effect of circ_0079593 on melanoma tumor growth in vivo. Our results discovered that circ_0079593 was highly expressed in melanoma, and its silencing suppressed melanoma cell proliferation, migration, invasion, glucose metabolism and promoted apoptosis. Moreover, we found that circ_0079593 could serve as a sponge of miR-516b, and miR-516b could target GRM3 in melanoma. The rescue experiments revealed that both miR-516b inhibitor and GRM3 overexpression could reverse the inhibition effect of circ_0079593 knockdown on melanoma progression. Additionally, in vivo experiments also revealed that circ_0079593 interference suppressed melanoma tumor growth. Our study concluded that circ_0079593 accelerated melanoma progression via upregulating GRM3 by sponging miR-516b, which suggested that circ_0079593 had the potential to be a new therapeutic biomarker for melanoma.

Defining the Prognostic Role of MicroRNAs in Cutaneous Melanoma

Breslow thickness (BT) is the most important histopathologic factor for primary melanoma staging. BT determines the margins for wide local excision whether sentinel lymph node biopsy should be performed and subsequent melanoma staging, and patient management. The correct determination of a 0.8-mm cutoff in melanoma is important for pathologists because discrepancies leading to a change in stage can have significant clinical implications, including incorrect and/or inappropriate prognostic information, investigation, management, and follow-up. Difficulties in BT determination are mostly represented by the presence of regression or melanoma associated with a pre-existing nevus. This study aimed at investigating a molecular parameter, namely microRNA (miRNA) expression, in reference to BT assessment. Melanoma cell proliferation is influenced by miRNA dysregulation. Indeed, some miRNAs sustain and induce proliferative signals or repress growth-suppressive pathways, thereby promoting melanoma carcinogenesis. To identify the miRNAs correlating with BT, we analyzed our global miRNA expression data of 20 thin melanomas and identified two potential candidates, miR-21-5p and miR-146a-5p. We assessed the expression of these two specific miRNAs in 90 archive formalin-fixed and paraffin-embedded samples of superficially spreading melanomas (SSMs) and 25 nodular melanomas from two independent cohorts and correlated the individual and combined miRNA expression with BT and other tumor characteristics. The individually normalized expression of miR-21-5p and miR-146a-5p showed a highly significant and linear correlation with BT in SSM, and their combined expression value was more strongly correlated (Pearson's r = 0.799, 95% CI = 0.71-0.86) than their individual expressions. This correlation was not significant in nodular melanoma. In SSM, we observed that the combined miRNA expression above or below 1.5 was significantly associated with overall survival and successfully identified all patients with relapsing SSM. We concluded that the combined assessment of miR-21-5p and miR-146a-5p expression in superficially spreading melanoma, in association with BT measurement, could aid pathologists in SSM staging.

Oxidative Phosphorylation Promotes Primary Melanoma Invasion

Dermal invasion is a hallmark of malignant melanoma. Although the molecular alterations that drive the progression of primary melanoma to metastatic disease have been studied extensively, the early progression of noninvasive primary melanoma to an invasive state is poorly understood. To elucidate the mechanisms underlying the transition from radial to vertical growth, the first step in melanoma invasion, we developed a zebrafish melanoma model in which constitutive activation of ribosomal protein S6 kinase A1 drives tumor invasion. Transcriptomic analysis of ribosomal protein S6 kinase A1-activated tumors identified metabolic changes, including up-regulation of genes associated with oxidative phosphorylation. Vertical growth phase human melanoma cells show higher oxygen consumption and preferential utilization of glutamine compared to radial growth phase melanoma cells. Peroxisome proliferator activated receptor γ coactivator (PGC)-1α, has been proposed as a master regulator of tumor oxidative phosphorylation. In human primary melanoma specimens, PGC1α protein expression was found to be positively associated with increased tumor thickness and expression of the proliferative marker Ki-67 and the reactive oxygen species scavenger receptor class A member 3. PGC1α depletion modulated cellular processes associated with primary melanoma growth and invasion, including oxidative stress. These results support a role for PGC1α in mediating glutamine-driven oxidative phosphorylation to facilitate the invasive growth of primary melanoma.

Inflammatory breast cancer cells are characterized by abrogated TGFβ1-dependent cell motility and SMAD3 activity

PURPOSE

Inflammatory breast cancer (IBC) is an aggressive form of breast cancer with elevated metastatic potential, characterized by tumor emboli in dermal and parenchymal lymph vessels. This study has investigated the hypothesis that TGFβ signaling is implicated in the molecular biology of IBC.

METHODS

TGFβ1-induced cell motility and gene expression patterns were investigated in three IBC and three non-IBC (nIBC) cell lines. Tissue samples from IBC and nIBC patients were investigated for the expression of nuclear SMAD2, SMAD3, and SMAD4. SMAD protein levels were related to gene expression data.

RESULTS

TGFβ1-induced cell motility was strongly abrogated in IBC cells (P = 0.003). Genes differentially expressed between IBC and nIBC cells post TGFβ1 exposure revealed attenuated expression of SMAD3 transcriptional regulators, but overexpression of MYC target genes in IBC. IBC patient samples demonstrated a near absence of SMAD3 and -4 expression in the primary tumor compared to nIBC patient samples (P < 0.001) and a further reduction of staining intensity in tumor emboli. Integration of gene and protein expression data revealed that a substantial fraction of the IBC signature genes correlated with SMAD3 and these genes are indicative of attenuated SMAD3 signaling in IBC.

CONCLUSION

We demonstrate attenuated SMAD3 transcriptional activity and SMAD protein expression in IBC, together with obliterated TGFβ1-induced IBC cell motility. The further reduction of nuclear SMAD expression levels in tumor emboli suggests that the activity of these transcription factors is involved in the metastatic dissemination of IBC cells, possibly by enabling collective invasion after partial EMT.

Epigenetic Silencing of CDR1as Drives IGF2BP3-Mediated Melanoma Invasion and Metastasis

Metastasis is the primary cause of death of cancer patients. Dissecting mechanisms governing metastatic spread may uncover important tumor biology and/or yield promising therapeutic insights. Here, we investigated the role of circular RNAs (circRNA) in metastasis, using melanoma as a model aggressive tumor. We identified silencing of cerebellar degeneration-related 1 antisense (CDR1as), a regulator of miR-7, as a hallmark of melanoma progression. CDR1as depletion results from epigenetic silencing of LINC00632, its originating long non-coding RNA (lncRNA) and promotes invasion in vitro and metastasis in vivo through a miR-7-independent, IGF2BP3-mediated mechanism. Moreover, CDR1as levels reflect cellular states associated with distinct therapeutic responses. Our study reveals functional, prognostic, and predictive roles for CDR1as and expose circRNAs as key players in metastasis.

MicroRNA Ratios Distinguish Melanomas from Nevi

The use of microRNAs as biomarkers has been proposed for many diseases, including the diagnosis of melanoma. Although hundreds of microRNAs have been identified as differentially expressed in melanomas as compared to benign melanocytic lesions, a limited consensus has been achieved across studies, constraining the effective use of these potentially useful markers. In this study, we applied a machine learning-based pipeline to a dataset consisting of genetic features, clinical features, and next-generation microRNA sequencing from micro-dissected formalin-fixed paraffin embedded melanomas and their adjacent benign precursor nevi. We identified patient age and tumor cellularity as variables that frequently confound the measured expression of potentially diagnostic microRNAs. By employing the ratios of microRNAs that were either enriched or depleted in melanoma compared to the nevi as a normalization strategy, we developed a model that classified all the available published cohorts with an area under the receiver operating characteristic curve of 0.98. External validation on an independent cohort classified lesions with 81% sensitivity and 88% specificity and was uninfluenced by the tumor content of the sample or patient age.

Pimozide suppresses cancer cell migration and tumor metastasis through binding to ARPC2, a subunit of the Arp2/3 complex

ARPC2 is a subunit of the Arp2/3 complex, which is essential for lamellipodia, invadopodia and filopodia, and ARPC2 has been identified as a migrastatic target molecule. To identify ARPC2 inhibitors, we generated an ARPC2 knockout DLD-1 human colon cancer cell line using the clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) system and explored gene signature-based strategies, such as a connectivity map (CMap) using the gene expression profiling data of ARPC2 knockout and knockdown cells. From the CMap-based drug discovery strategy, we identified pimozide (a clinically used antipsychotic drug) as a migrastatic drug and ARPC2 inhibitor. Pimozide inhibited the migration and invasion of various cancer cells. Through drug affinity responsive target stability (DARTS) analysis and cellular thermal shift assay (CETSA), it was confirmed that pimozide directly binds to ARPC2. Pimozide increased the lag phase of Arp2/3 complex-dependent actin polymerization and inhibited the vinculin-mediated recruitment of ARPC2 to focal adhesions in cancer cells. To validate the likely binding of pimozide to ARPC2, mutant cells, including ARPC2^F225A , ARPC2^F247A and ARPC2^Y250F cells, were prepared using ARPC2 knockout cells prepared by gene-editing technology. Pimozide strongly inhibited the migration of mutant cells because the mutated ARPC2 likely has a larger binding pocket than the wild-type ARPC2. Therefore, pimozide is a potential ARPC2 inhibitor, and ARPC2 is a new molecular target. Taken together, the results of the present study provide new insights into the molecular mechanism and target that are responsible for the antitumor and antimetastatic activity of pimozide.

Novel MicroRNA Biomarkers, miR-142-5p, miR-550a, miR-1826, and miR-1201, Were Identified for Primary Melanoma

This study was aimed to identify novel miRNA biomarkers and explore the cooperative function of multi-RNAs in the progress of primary melanoma. The miRNA expression profile GSE62370 generated from 9 congenital nevi and 92 primary melanoma samples was downloaded from the Gene Expression Omnibus database. Differentially expressed miRNAs between primary melanoma and congenital nevi were compared and the target genes of them were selected. Pathway enrichment analysis and protein/protein interaction (PPI) network of miRNA target genes were performed. In addition, the differential expression of miRNAs to identify the tumor stage-dependent differences in miRNA expression was analyzed. Differentially expressed miRNAs, including 6 upregulated and 23 downregulated, were found in primary melanoma. Besides, the miRNA-associated gene regulatory network revealed 274 nodes, including miR-142-5p and miR-125b, and 307 miRNA-target pairs. miRNA-related Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, such as melanoma, was found. Target genes in the PPI module were mainly enriched in cancer-related pathways. Finally, the melanoma stage-related overexpressed miR-142-5p and the downregulated miR-550, miR-1826, miR-1201, miR-205, and miR-125b were identified. Some validated miRNAs, including miR-125a/b, let-7a/b, and miR-205, were found and illustrated the reliability of our study. Four novel miRNAs, including miR-142-5p, miR-550a, miR-1826, and miR-1201, were considered to have potential prognostic values for primary melanoma.

Melanoma Explorer: a web application to allow easy reanalysis of publicly available and clinically annotated melanoma omics data sets

Validating newly discovered biomarkers in large, publicly available data sets is often difficult and requires specialized computer programming skills. Melanoma Explorer is a web application that enables easy interrogation of melanoma omics data sets that are freely available in online data repositories with a point-and-click interface. Two use cases are demonstrated. First, the relationship of lysozyme mRNA expression is shown to be prognostic in two independent gene expression microarray data sets. Second, a figure from a journal article showing the relationship of tumour thickness and miR-382 abundance is reproduced. Melanoma Explorer is demonstrated to be a useful tool for reproducing results of published studies and providing additional evidence for biomarkers in independent data sets.

The role of miR-382-5p in glioma cell proliferation, migration and invasion

Background: Dysregulation of a single miRNA can play an essential role in tumor development and progression. Recent studies have shown that miR-382-5p can function as an oncogene or as a tumor suppressor in different types of cancers. However, the role of miR-382-5p in glioma growth and expansion has not been characterized.

Methods: Quantitative real time-PCR (qRT-PCR) was used to measure miR-382-5p levels in glioma tissues. The miR-382-5p mimics and inhibitors were employed to upregulate and downregulate miR-382-5p expression respectively in glioma cells. EdU assay was used to assess cell proliferation. Wound healing and Transwell assays were employed to evaluate cell migration and invasion. Western blot was used to measure the changes of epithelial-to-mesenchymal transition (EMT) markers and the potential miR-382-5p target genes.

Results: We found that miR-382-5p levels were low in glioma tissues as determined by qRT-PCR. EdU assay showed that upregulation of miR-382-5p significantly decreased cell proliferation in both U87 and U251 cells. Wound healing rate was significantly decreased in response to miR-382-5p mimics and significantly increased in response to miR-382-5p inhibitors. Transwell migration assays further confirmed the inhibitory effects of miR-382-5p on the migration in both U251 and U87 cells. Transwell invasion assays showed that upregulation of miR-382-5p resulted in a remarkable decrease in the number of invading cells, whereas downregulation of miR-382-5p led to a significant increase in the numbers of invading U87 and U251 cells. In addition, overexpression of miR-382-5p decreased the protein levels of N-cadherin, Snail and Slug, and increased E-cadherin levels, in glioma cells. Furthermore, miR-382-5p levels negatively correlated with Y box-binding protein 1 (YBX1) in lower grade glioma tissues, and negatively regulated the expression of YBX1 in glioma cells.

Conclusion: In summary, miR-382-5p inhibited proliferation, migration, invasion, and the EMT in glioma cells, possibly through targeting the oncogene YBX1.

MicroRNA heterogeneity in melanoma progression

The altered expression of miRNAs has been linked with neocarcinogenesis or the development of human malignancies including melanoma. Of significance, multiple clinical studies have documented that distinct sets of microRNAs (miRNAs) could be utilized as prognostic biomarkers for cancer development or predict the outcomes of treatment responses. To that end, an in-depth validation of such differentially expressed miRNAs is necessary in diverse settings of cancer patients in order to devise novel approaches to control tumor growth and/or enhance the efficacy of clinically-relevant therapeutic options. Moreover, considering the heterogeneity and sophisticated regulation of miRNAs, the precise delineation of their cellular targets could also be explored to design personalized medicine. Given the significance of miRNAs in regulating several key cellular processes of tumor cells including cell cycle progression and apoptosis, we review the findings of such miRNAs implicated in melanoma tumorigenesis. Understanding the novel mechanistic insights of such miRNAs will be useful for developing diagnostic or prognostic biomarkers or devising future therapeutic intervention for malignant melanoma.

Non-coding RNA MFI2-AS1 promotes colorectal cancer cell proliferation, migration and invasion through miR-574-5p/MYCBP axis

Objective

Long non‐coding RNAs (lncRNAs) and microRNAs (miRNAs) play essential roles in the tumour progression. LncRNAs mostly act as competing endogenous RNAs (ceRNAs) by sponging miRNAs. This study aimed to study the association of a novel lncRNA MFI2‐AS1 with miR‐574‐5p/MYCBP axis in the development of colorectal cancer (CRC).

Methods

Ninety‐four CRC tissues and paired adjacent non‐tumour tissues were included in our study. The relative expression level of MFI2‐AS1 was detected, and its relationship with clinico‐pathological factors was analysed. Then, the CRC cells lines (LoVo and RKO) were transfected with MFI2‐AS1 siRNA, miR‐574‐5p mimics and inhibitors. Cell proliferation, migration, invasion, cell cycle distribution and DNA damage in response to different transfection conditions were examined. Dual‐luciferase reporter assay was performed to identify the target interactions between MFI2‐AS1 and miR‐574‐5p, miR‐574‐5p and MYCBP.

Results

LncRNA MFI2‐AS1 and MYCBP were up‐regulated in CRC tissues when compared with adjacent non‐tumour tissues. The expression levels of MFI2‐AS1 were significantly associated with tumour histological grade, lymph and distant metastasis, TNM stage and vascular invasion. Both MFI2‐AS1 siRNA and miR‐574‐5p mimics inhibited proliferation, migration and invasion in LoVo and RKO cells. The transfection of miR‐574‐5p inhibitor showed MFI2‐AS1 siRNA‐induced changes in CRC cells. Dual‐luciferase reporter assay revealed target interactions between MFI2‐AS1 and miR‐574‐5p, miR‐574‐5p and MYCBP.

Conclusions

These findings suggested that lncRNA MFI2‐AS1 and MYCBP have promoting effects in CRC tissues. LncRNA MFI2‐AS1 promoted CRC cell proliferation, migration and invasion through activating MYCBP and by sponging miR‐574‐5p.

Interplay between small and long non-coding RNAs in cutaneous melanoma: a complex jigsaw puzzle with missing pieces

The incidence of cutaneous melanoma (CM) has increased in the past few decades. The biology of melanoma is characterized by a complex interaction between genetic, environmental and phenotypic factors. A greater understanding of the molecular mechanisms that promote melanoma cell growth and dissemination is crucial to improve diagnosis, prognostication, and treatment of CM. Both small and long non-coding RNAs (lncRNAs) have been identified to play a role in melanoma biology; microRNA and lncRNA expression is altered in transformed melanocytes and this in turn has functional effects on cell proliferation, apoptosis, invasion, metastasis, and immune response. Moreover, specific dysregulated ncRNAs were shown to have a diagnostic or prognostic role in melanoma and to drive the establishment of drug resistance. Here, we review the current literature on small and lncRNAs with a role in melanoma, with the aim of putting into some order this complex jigsaw puzzle.

C-X-C Motif Ligand 1 (CXCL1) from melanoma cells down-regulates the invasion of their metastatic melanoma cells

The surgical resection of a primary melanoma is sometimes followed by the immediate development of distant metastases, suggesting that the primary melanoma might control the metastatic process. We hypothesized that a paracrine factor(s) from primary melanoma cells might regulate the progression of metastasizing melanoma cells. Here we attempted to identify the factor(s) from primary melanoma cells that regulate the invasion ability of metastatic melanoma cells. We used two mouse melanoma cell lines, B16 and B16/BL6, that latter of which is a subline of B16 melanoma and shows high metastatic potential to lung. We investigated the interaction between the parent B16 cells and daughter B16/BL6 cells by invasion assay, cell morphology, cytokine array, RT-PCR, and gelatin-zymography. The conditioned medium (CM) from B16 significantly (p=0.02) inhibited the invasion ability of B16/BL6 cells. The morphology of the B16/BL6 cells was changed from bipolar shape to a multipolar shape following the addition of the CM from B16. The B16 cells produced high levels of C-X-C motif ligand 1 (CXCL1), CXCL10, and M-CSF compared to the B16/BL6 cells. CXCL1 significantly (p=0.01) decreased the invasion ability of B16/BL6 cells, but CXCL10 and M-CSF did not. The invasion-inhibitory activity of the CM from B16 was significantly (p=0.046) suppressed following the addition of a neutralizing anti-CXCL1 antibody. The CM of B16 and CXCL1 increased the E-cadherin mRNA level and decreased MMP2 activity of B16/BL6 cells. These findings suggested that primary melanoma cells might down-regulate the invasion activity of metastatic melanoma cells through CXCL1 signaling.

MicroRNAs in cutaneous melanoma: Role as diagnostic and prognostic biomarkers

Melanoma is the leading cause of skin cancer deaths in the United States, and its incidence has been rising steadily for the past 30 years (Aftab, Dinger, & Perera, 2014). A more complete understanding of the molecular mechanisms that drive melanomagenesis is crucial to improve diagnosis, prognostication, and treatment of this disease. Given that melanoma survival rates are better when the disease is detected early, precise diagnostic tests for early melanoma detection would be extremely useful. In addition, as survival rates decrease drastically when the disease becomes metastatic, improved tools to more precisely identify high-risk patients as well as to predict treatment response are necessary. The role of microRNAs (miRNAs) in melanoma biology could be the key. miRNA expression profiling has identified several miRNAs that play a crucial role in melanoma cell proliferation, migration, and invasion, as well as miRNAs involved in apoptosis and in the immune response. Here we review the most current data on the miRNAs involved in melanoma as well as their potential roles as diagnostic and prognostic biomarkers of this disease.

Context-dependent miR-204 and miR-211 affect the biological properties of amelanotic and melanotic melanoma cells

Despite increasing amounts of experimental evidence depicting the involvement of non-coding RNAs in cancer, the study of BRAFV600E-regulated genes has thus far focused mainly on protein-coding ones. Here, we identify and study the microRNAs that BRAFV600E regulates through the ERK pathway.

By performing small RNA sequencing on A375 melanoma cells and a vemurafenib-resistant clone that was taken as negative control, we discover miR-204 and miR-211 as the miRNAs most induced by vemurafenib. We also demonstrate that, although belonging to the same family, these two miRNAs have distinctive features. miR-204 is under the control of STAT3 and its expression is induced in amelanotic melanoma cells, where it acts as an effector of vemurafenib's anti-motility activity by targeting AP1S2. Conversely, miR-211, a known transcriptional target of MITF, is induced in melanotic melanoma cells, where it targets EDEM1 and consequently impairs the degradation of TYROSINASE (TYR) through the ER-associated degradation (ERAD) pathway. In doing so, miR-211 serves as an effector of vemurafenib's pro-pigmentation activity. We also show that such an increase in pigmentation in turn represents an adaptive response that needs to be overcome using appropriate inhibitors in order to increase the efficacy of vemurafenib.

In summary, we unveil the distinct and context-dependent activities exerted by miR-204 family members in melanoma cells. Our work challenges the widely accepted “same miRNA family = same function” rule and provides a rationale for a novel treatment strategy for melanotic melanomas that is based on the combination of ERK pathway inhibitors with pigmentation inhibitors.

High intensity focused ultrasound inhibits melanoma cell migration and metastasis through attenuating microRNA-21-mediated PTEN suppression

High intensity focused ultrasound (HIFU) technology is becoming a potential noninvasive treatment for solid tumor. To explore whether HIFU can be applied to treat melanoma and its metastasis, we investigated the effect of HIFU on murine melanoma model. While there was little influence on cell survival, viability or apoptosis, HIFU exposure suppressed melanoma cell migration in vitro and metastasis in vivo. The expression of microRNA-21(miR-21) was down-regulated and PTEN expression was up-regulated in response to HIFU exposure, which was in concomitant with the reduction of AKT activity. Furthermore, ectopic miR-21 expression suppressed this effect of HIFU. These results demonstrate that HIFU exposure can inhibit AKT-mediated melanoma metastasis via miR-21 inhibition to restore PTEN expression. Therefore, targeting the miR-21/PTEN/AKT pathway might be a novel strategy of HIFU in treatment of melanoma.

microRNA-7-5p inhibits melanoma cell proliferation and metastasis by suppressing RelA/NF-κB

microRNA-7-5p (miR-7-5p) is a tumor suppressor in multiple cancer types and inhibits growth and invasion by suppressing expression and activity of the epidermal growth factor receptor (EGFR) signaling pathway. While melanoma is not typically EGFR-driven, expression of miR-7-5p is reduced in metastatic tumors compared to primary melanoma. Here, we investigated the biological and clinical significance of miR-7-5p in melanoma. We found that augmenting miR-7-5p expression in vitro markedly reduced tumor cell viability, colony formation and induced cell cycle arrest. Furthermore, ectopic expression of miR-7-5p reduced migration and invasion of melanoma cells in vitro and reduced metastasis in vivo. We used cDNA microarray analysis to identify a subset of putative miR-7-5p target genes associated with melanoma and metastasis. Of these, we confirmed nuclear factor kappa B (NF-κB) subunit RelA, as a novel direct target of miR-7-5p in melanoma cells, such that miR-7-5p suppresses NF-κB activity to decrease expression of canonical NF-κB target genes, including IL-1β, IL-6 and IL-8. Importantly, the effects of miR-7-5p on melanoma cell growth, cell cycle, migration and invasion were recapitulated by RelA knockdown. Finally, analysis of gene array datasets from multiple melanoma patient cohorts revealed an association between elevated RelA expression and poor survival, further emphasizing the clinical significance of RelA and its downstream signaling effectors. Taken together, our data show that miR-7-5p is a potent inhibitor of melanoma growth and metastasis, in part through its inactivation of RelA/NF-κB signaling. Furthermore, miR-7-5p replacement therapy could have a role in the treatment of this disease.

MicroRNAs in melanoma development and resistance to target therapy

microRNAs constitute a complex class of pleiotropic post-transcriptional regulators of gene expression involved in the control of several physiologic and pathologic processes. Their mechanism of action is primarily based on the imperfect matching of a seed region located at the 5′ end of a 21-23 nt sequence with a partially complementary sequence located in the 3′ untranslated region of target mRNAs. This leads to inhibition of mRNA translation and eventually to its degradation. Individual miRNAs are capable of binding to several mRNAs and several miRNAs are capable of influencing the function of the same mRNAs. In recent years networks of miRNAs are emerging as capable of controlling key signaling pathways responsible for the growth and propagation of cancer cells. Furthermore several examples have been provided which highlight the involvement of miRNAs in the development of resistance to targeted drug therapies. In this review we provide an updated overview of the role of miRNAs in the development of melanoma and the identification of the main downstream pathways controlled by these miRNAs. Furthermore we discuss a group of miRNAs capable to influence through their respective up- or down-modulation the development of resistance to BRAF and MEK inhibitors.

MicroRNA-382-5p aggravates breast cancer progression by regulating the RERG/Ras/ERK signaling axis

Aberrant activation of the Ras/ERK pathway mediates breast cancer initiation and aggressiveness. Therefore, it is important to identify miRNAs that modulate the Ras/ERK pathway during breast carcinogenesis and progression. The Ras GTPase superfamily member RERG (Ras-related and estrogen-regulated growth inhibitor) acts as a tumor suppressor to reduce breast cancer cell proliferation and tumor formation and has been suggested to have a regulatory role in the Ras/ERK pathway. In this study, we found that RERG exerted its tumor suppressor role by attenuating the activation of Ras/ERK signaling effectors. Furthermore, we found that miR-382-5p directly targets and represses RERG to attenuate the inhibitory effects of RERG on the oncogenic Ras/ERK pathway. Thereby, miR-382-5p promoted breast cancer cell viability, clonogenicity, survival, migration, invasion and in vivo tumorigenesis/metastasis. In clinical interpretation, miR-382-5p expression was negatively correlated with RERG expression, and it also significantly functioned as an independent oncomiR for the higher incidence and poorer prognosis of breast cancer. This novel connection highlights new diagnostic and prognostic roles for miR-382-5p and RERG in breast cancer.

miR-382 targeting PTEN-Akt axis promotes liver regeneration

Liver regeneration is a highly orchestrated process which can be regulated by microRNAs (miRNAs, miRs), though the mechanisms are largely unclear. This study was aimed to identify miRNAs responsible for hepatocyte proliferation during liver regeneration. Here we detected a marked elevation of miR-382 in the mouse liver at 48 hrs after partial hepatectomy (PH-48h) using microarray analysis and qRT-PCRs. miR-382 overexpression accelerated the proliferation and the G1 to S phase transition of the cell cycle both in mouse NCTC1469 and human HL7702 normal liver cells, while miR-382 downregulation had inverse effects. Moreover, miR-382 negatively regulated PTEN expression and increased Akt phosphorylation both in vitro and in vivo. Using PTEN siRNA and Akt activator/inhibitor, we further found that PTEN inhibition and Akt phosphorylation were essential for mediating the promotive effect of miR-382 in the proliferation and cell growth of hepatocytes. Collectively, our findings identify miR-382 as a promoter for hepatocyte proliferation and cell growth via targeting PTEN-Akt axis which might be a novel therapeutic target to enhance liver regeneration capability.

MicroRNA-382 inhibits prostate cancer cell proliferation and metastasis through targeting COUP-TFII

MicroRNAs (miRNAs) have emerged as important regulators in cancer that are implicated in regulation of various cellular processes. miR-382 has been proposed as a tumor suppressor by several recent studies. However, the function of miR-382 in prostate cancer remains unknown. In this study, we aimed to investigate the potential function of miR-382 in prostate cancer. We found that miR-382 was significantly decreased in prostate cancer specimens and cancer cell lines. The overexpression of miR-382 in prostate cancer cells markedly inhibited cell proliferation, migration, and invasion. In contrast, miR-382 suppression exhibited an opposite effect. Target analysis predicted that chicken ovalbumin upstream promoter transcription factor II (COUP‑TFII) was a direct target of miR-382. This prediction was experimentally confirmed by dual-luciferase reporter assay, real-time quantitative polymerase chain reaction, and western blot analysis. Our results further demonstrated that miR-382 inhibited the downstream genes of COUP‑TFII, including Snail and matrix metalloproteinase 2 (MMP2). Moreover, the restoration of COUP‑TFII expression significantly blocked the inhibitory effect of miR-382 on cell proliferation, migration, and invasion, and Snail expression. Taken together, this study suggests that miR-382 inhibits prostate cancer cell proliferation and metastasis through inhibiting COUP‑TFII, representing an important new mechanism for understanding prostate cancer pathogenesis and providing a novel therapeutic candidate target for prostate cancer therapy.

The Inescapable Influence of Noncoding RNAs in Cancer

This report summarizes information presented at the 2015 Keystone Symposium on "MicroRNAs and Noncoding RNAs in Cancer." Nearly two decades after the discovery of the first miRNA, the role of noncoding RNAs in developmental processes and the mechanisms behind their dysregulation in cancer has been steadily elucidated. Excitingly, miRNAs have begun making their way into the clinic to combat diseases such as hepatitis C and various forms of cancer. Therefore, at this Keystone meeting, novel findings were presented that enhance our view on how small and long noncoding RNAs control developmental timing and oncogenic processes. Recurring themes included (i) how miRNAs can be differentially processed, degraded, and regulated by ribonucleoprotein complexes, (ii) how particular miRNA genetic networks that control developmental process, when disrupted, can result in cancer disease, (iii) the technologies available to therapeutically deliver RNA to combat diseases such as cancer, and (iv) the elucidation of the mechanism of actions for long noncoding RNAs, currently a poorly understood class of noncoding RNA. During the meeting, there was an emphasis on presenting unpublished findings, and the breadth of topics covered reflected how inescapable the influence of noncoding RNAs is in development and cancer.

Revisiting determinants of prognosis in cutaneous melanoma

The American Joint Committee on Cancer staging system for cutaneous melanoma is based on primary tumor thickness and the presence of ulceration, mitoses, lymph node spread, and distant metastases as determinants of prognosis. Although this cutaneous melanoma staging system has evolved over time to more accurately reflect patient prognosis, improvements are still needed, because current understanding of the particular factors (genetic mutation, expression alteration, host response, etc) that are critical for predicting patient outcomes is incomplete. Given the clinical and biologic heterogeneity of primary melanomas, new prognostic tools are needed to more precisely identify patients who are most likely to develop advanced disease. Such tools would affect clinical surveillance strategies and aid in patient selection for adjuvant therapy. The authors reviewed the literature on prognostic molecular and immunologic markers in primary cutaneous melanoma, their associations with clinicopathologic and survival outcomes, and their potential for incorporation into current staging models. Overall, the studies considered in this review did not define prognostic markers that could be readily incorporated into the current staging system. Therefore, efforts should be continued in these and other directions to maximize the likelihood of identifying clinically useful prognostic biomarkers for cutaneous melanoma.