Comprehensive Review on the Clinical Relevance of Long Non-Coding RNAs in Cutaneous Melanoma

Lnc-PKNOX1-1 inhibits tumor progression in cutaneous malignant melanoma by regulating NF-κB/IL-8 axis

Cutaneous malignant melanoma is one of the most lethal cutaneous malignancies. Accumulating evidence has demonstrated the potential influence of long non-coding RNAs (lncRNAs) in biological behaviors of melanoma. Herein, we reported a novel lncRNA, lnc-PKNOX1-1 and systematically studied its functions and possible molecular mechanisms in melanoma. Reverse transcription-quantitative PCR assay showed that lnc-PKNOX1-1 was significantly decreased in melanoma cells and tissues. Low lnc-PKNOX1-1 expression was significantly correlated with invasive pathological type and Breslow thickness of melanoma. In vitro and in vivo experiments showed lnc-PKNOX1-1 dramatically inhibited melanoma cell proliferation, migration and invasion. Mechanically, protein microarray analysis suggested that interleukin-8 (IL-8) was negatively regulated by lnc-PKNOX1-1 in melanoma, which was confirmed by western blot and ELISA. Western blot analysis also showed that lnc-PKNOX1-1 could promote p65 phosphorylation at Ser536 in melanoma. Subsequent rescue assays proved IL-8 overexpression could partly reverse the tumor-suppressing function of lnc-PKNOX1-1 overexpression in melanoma cells, indicating that lnc-PKNOX1-1 suppressed the development of melanoma by regulating IL-8. Taken together, our study demonstrated the tumor-suppressing ability of lnc-PKNOX1-1 in melanoma, suggesting its potential as a novel diagnostic biomarker and therapeutic target for melanoma.

BRAF Mutations in Melanoma: Biological Aspects, Therapeutic Implications, and Circulating Biomarkers

Melanoma is an aggressive form of skin cancer resulting from the malignant transformation of melanocytes. Recent therapeutic approaches, including targeted therapy and immunotherapy, have improved the prognosis and outcome of melanoma patients. BRAF is one of the most frequently mutated oncogenes recognised in melanoma. The most frequent oncogenic BRAF mutations consist of a single point mutation at codon 600 (mostly V600E) that leads to constitutive activation of the BRAF/MEK/ERK (MAPK) signalling pathway. Therefore, mutated BRAF has become a useful target for molecular therapy and the use of BRAF kinase inhibitors has shown promising results. However, several resistance mechanisms invariably develop leading to therapeutic failure. The aim of this manuscript is to review the role of BRAF mutational status in the pathogenesis of melanoma and its impact on differentiation and inflammation. Moreover, this review focuses on the mechanisms responsible for resistance to targeted therapies in BRAF-mutated melanoma and provides an overview of circulating biomarkers including circulating tumour cells, circulating tumour DNA, and non-coding RNAs.

A novel cuproptosis-related lncRNA prognostic signature in thyroid cancer

Aims: We aimed to investigate the value of cuproptosis-related lncRNA in screening out high-risk thyroid cancer patients. Materials & methods: RNA sequencing data of thyroid cancer were obtained from The Cancer Genome Atlas. A cuproptosis-related lncRNA signature was constructed by using Cox regression. Results: Four cuproptosis-related lncRNAs were used to construct a survival prognosis model for thyroid cancer. The receiver operating characteristic curve showed that the area under the curve reached 0.830 at 1 year, 0.790 at 3 years and 0.824 at 5 years. Conclusion: The model may help to screen out thyroid cancer patients at high risk, and thus develop more appropriate treatment strategies.

Long non-coding RNA CCHE1 modulates LDHA-mediated glycolysis and confers chemoresistance to melanoma cells

Melanoma is considered as the most common metastatic skin cancer with increasing incidence and high mortality globally. The vital roles of long non-coding RNAs (lncRNAs) in the tumorigenesis of melanoma are elucidated by emerging evidence. The lncRNA cervical carcinoma high-expressed 1 (CCHE1) was overexpressed and acted as an oncogene in a variety of cancers, while the function of CCHE1 in melanoma remains unclear. Here, we found that CCHE1 was highly expressed in melanoma and correlated with the poorer survival of melanoma patients. Depletion of CCHE1 inhibited the proliferation, induced cell apoptosis and suppressed in vivo tumor growth. To further understand the functional mechanism of CCHE1, the interacting partners of CCHE1 were identified via RNA pull-down assay followed by mass spectrometry. CCHE1 was found to bind lactate dehydrogenase A (LDHA) and acted as a scaffold to enhance the interaction of LDHA with the fibroblast growth factor receptor type 1 (FGFR1), which consequently enhanced LDHA phosphorylation and activity of LDHA. Inhibiting CCHE1 strikingly suppressed the glycolytic flux of melanoma cells and lactate generation in vivo. Further study demonstrated that CCHE1 desensitized melanoma cells to dacarbazine and inhibition of glycolysis reversed CCHE1-induced chemoresistance. These results uncovered the novel function of CCHE1 in melanoma by reprogramming the glucose metabolism via orchestrating the activity of LDHA.

A novel risk model based on cuproptosis-related lncRNAs predicted prognosis and indicated immune microenvironment landscape of patients with cutaneous melanoma

Cutaneous melanoma (CM) is an aggressive form of malignancy with poor prognostic value. Cuproptosis is a novel type of cell death regulatory mechanism in tumors. However, the role of cuproptosis-related long noncoding RNAs (lncRNAs) in CM remains elusive. The cuproptosis-related lncRNAs were identified using the Pearson correlation algorithm. Through the univariate and multivariate Cox regression analysis, the prognosis of seven lncRNAs associated with cuproptosis was established and a new risk model was constructed. ESTIMATE, CIBERSORT, and single sample gene set enrichment analyses (ssGSEA) were applied to evaluate the immune microenvironment landscape. The Kaplan–Meier survival analysis revealed that the overall survival (OS) of CM patients in the high-risk group was remarkably lower than that of the low-risk group. The result of the validated cohort and the training cohort indicated that the risk model could produce an accurate prediction of the prognosis of CM. The nomogram result demonstrated that the risk score based on the seven prognostic cuproptosis-related lncRNAs was an independent prognostic indicator feature that distinguished it from other clinical features. The result of the immune microenvironment landscape indicated that the low-risk group showed better immunity than high-risk group. The immunophenoscore (IPS) and immune checkpoints results conveyed a better benefit potential for immunotherapy clinical application in the low-risk groups. The enrichment analysis and the gene set variation analysis (GSVA) were adopted to reveal the role of cuproptosis-related lncRNAs mediated by the immune-related signaling pathways in the development of CM. Altogether, the construction of the risk model based on cuproptosis-related lncRNAs can accurately predict the prognosis of CM and indicate the immune microenvironment of CM, providing a new perspective for the future clinical treatment of CM.

The Emerging Role of Long Non-Coding RNAs in Esophageal Cancer: Functions in Tumorigenesis and Clinical Implications

Esophageal cancer (EC) is one of the most common malignancies of digestive tracts with poor five-year survival rate. Hence, it is very significant to further investigate the occurrence and development mechanism of esophageal cancer, find more effective biomarkers and promote early diagnosis and effective treatment. Long non-coding RNAs (lncRNAs) are generally defined as non-protein-coding RNAs with more than 200 nucleotides in length. Existing researches have shown that lncRNAs could act as sponges, guides, scaffolds, and signal molecules to influence the oncogene or tumor suppressor expressions at transcriptional, post-transcriptional, and protein levels in crucial cellular processes. Currently, the dysregulated lncRNAs are reported to involve in the pathogenesis and progression of EC. Importantly, targeting EC-related lncRNAs through genome editing, RNA interference and molecule drugs may be one of the most potential therapeutic methods for the future EC treatment. In this review, we summarized the biological functions and molecular mechanisms of lncRNAs, including oncogenic lncRNAs and tumor suppressor lncRNAs in EC. In addition, we generalized the excellent potential lncRNA candidates for diagnosis, prognosis and therapy in EC. Finally, we discussed the current challenges and opportunities of lncRNAs for EC.

Pathogenic roles of long noncoding RNAs in melanoma: Implications in diagnosis and therapies

Melanoma is one of the most dangerous types of cutaneous neoplasms, which are pigment-producing cells of neuroectodermal origin found all over the body. A great deal of research is focused on the mechanisms of melanoma to promote better diagnostic and treatment options for melanoma in its advanced stages. The progression of melanoma involves alteration in different levels of gene expression. With the successful implementation of next-generation sequencing technology, an increasing number of long noncoding RNAs (lncRNAs) sequences have been discovered, and a significant number of them have phenotypic effects in both in vitro and in vivo studies, implying that they play an important role in the occurrence and progression of human cancers, particularly melanoma. A number of evidence indicated that lncRNAs are important regulators in tumor cell proliferation, invasion, apoptosis, immune escape, energy metabolism, drug resistance, epigenetic regulation. To better understand the role of lncRNAs in melanoma tumorigenesis, we categorize melanoma-associated lncRNAs according to their cellular functions and associations with gene expression and signaling pathways in this review. Based on the mechanisms of lncRNA, we discuss the possibility of lncRNA-target treatments, and the application of liquid biopsies to detect lncRNAs in melanoma diagnosis and prognosis.

LncRNA LINC01116 facilitates melanoma 1 progression via sequestering miR-3612 and up-regulating GDF11 and SDC3

BACKGROUND

Melanoma is the deadliest cutaneous malignant tumor with high risks. Though increasing evidence has widely referred to the involvement of long non-coding RNAs (lncRNAs) in the mechanism of tumor development, including melanoma, the functional roles of most lncRNAs in melanoma remain to be explored. In this study, we focus on disclosing the role of long intergenic non-protein coding RNA 1116 (LINC01116) in melanoma.

METHODS

Firstly, we detected LINC01116 expression through RT-qPCR. Functional analysis and animal experiments were carried out to assess the role of LINC01116 in vivo and in vitro. Western blot analysis was employed for detection of important markers regarding epithelial mesenchymal transition (EMT). In addition, RNA pulls down, RIP and luciferase reporter assays were performed to probe into the regulatory mechanism of LINC01116.

RESULTS

LINC01116 was significantly up regulated in melanoma cells. LINC01116 deficiency abrogated cell proliferation, migration, invasion and EMT in melanoma. Moreover, LINC01116 enhanced growth differentiation factor 11 (GDF11) and syndecan 3 (SDC3) expression through sponging microRNA-3612 (miR-3612). The oncogenic role of the LINC01116/miR-3612/GDF11/SDC3 axis in melanoma was finally demonstrated.

CONCLUSION

Conclusively, LINC01116 sequestered miR-3612 and targeted GDF11 and SDC3 to contribute to the progression of melanoma.