Analysis of clinical, dermoscopic and histopathological features of primary melanomas of patients with metastatic disease--a retrospective study at the Department of Dermatology, Medical University of Graz, 2000-2010

Development of anoikis-related long non-coding RNA signature associated with prognosis and immune landscape in cutaneous melanoma patients

BACKGROUND

Anoikis is involved in many critical biological processes in tumors; however, function in CM is still unknown. In this study, the relevance between Anoikis-related lncRNAs (ARLs) and the clinicopathological characteristics of patients with CM was comprehensively assessed.

METHODS

Through analysis of TCGA dataset, ARLs were identified by using TCGA dataset. Based on the ARLs, a risk model was established to anticipate the prognosis of patients with CM, besides, the prediction accuracy of the model was evaluated. The immune infiltration landscape of patients with CM was assessed comprehensively, and the correlation between ARLs and immunity was elucidated. Immunotherapy and drug sensitivity analyses were applied to analyze the treatment response in patients with CM with diverse risk scores. Different subgroups were distinguished among the patients using consensus cluster analysis.

RESULTS

A risk model based on six ARLs was set up to obtain an accurate prediction of the prognosis of patients with CM. There were distinctions in the immune landscape among CM patients with diverse risk scores and subgroups. Six prognosis-related ARLs were highly correlated with the number of immune cells. Patients with CM with different risk scores have various sensitivities to immunotherapy and antitumor drug treatments.

CONCLUSION

Our newly risk model associated with ARLs has considerable prognostic value for patients with CM. Not only has the risk model high prediction accuracy but it also indicates the immune status of CM patients, which will provide a new direction for the individualized therapy of patients with CM.

Dermoscopic Criteria, Histopathological Correlates and Genetic Findings of Thin Melanoma on Non-Volar Skin

Dermoscopy is a non-invasive, in vivo technique that allows the visualization of subsurface skin structures in the epidermis, at the dermoepidermal junction, and in the upper dermis. Dermoscopy brought a new dimension in evaluating melanocytic skin neoplasms (MSN) also representing a link between clinical and pathologic examination of any MSN. However, histopathology remains the gold standard in diagnosing MSN. Dermoscopic-pathologic correlation enhances the level of quality of MSN diagnosis and increases the level of confidence of pathologists. Melanoma is one of the most genetically predisposed among all cancers in humans. The genetic landscape of melanoma has been described in the last years but is still a field in continuous evolution. Melanoma genetic markers play a role not only in melanoma susceptibility, initiation, and progression but also in prognosis and therapeutic decisions. Several studies described the dermoscopic specific criteria and predictors for melanoma and their histopathologic correlates, but only a few studies investigated the correlation among dermoscopy, pathology, and genetic of MSN. The aim of this work is to review the published data about dermoscopic features of melanoma, their histopathological correlates with regards also to genetic alterations. Particularly, this review will focus on low-CSD (cumulative sun damage) melanoma or superficial spreading melanoma, high-CSD melanoma, and nevus-associated melanoma.

CircHIPK3 regulates melanoma cell behaviors by binding with miR-215-5p to upregulate YY1

OBJECT

To investigate the role of circHIPK3 in melanoma.

METHODS

Bioinformatics analysis and experiments including RT-qPCR, Pearson's correlation analysis, luciferase reporter, Western blot, and RIP assays were applied to explore the function and mechanism of circHIPK3 in melanoma.

RESULTS

CircHIPK3 expression was strikingly upregulated while miR-215-5p was downregulated in melanoma tissues and cell lines. Pearson's correlation analysis unveiled circHIPK3 expression was positively correlated with Ki-67 (a marker of proliferation), which implied that circHIPK3 may play a vital role in the progression of melanoma. In mechanism, luciferase reporter and RIP assays validated that circHIPK3 was able to bind with miR-215-5p. Moreover, we confirmed that overexpression of circHIPK3 could facilitate cell proliferation and depress cell apoptosis in melanoma while overexpression of miR-215-5p exerted opposite effects. Besides, our findings indicated that miR-215-5p overexpression significantly reversed the circHIPK3 overexpressing-mediated promotive effect on cell proliferation and inhibitory effect on cell apoptosis. Furthermore, we found that miR-215-5p could directly target YY1. Upregulation of YY1 could notably offset the inhibitory effect of circHIPK3 downregulation on cell proliferation and the promotive effect on cell apoptosis.

CONCLUSION

Our study corroborated that circHIPK3 regulated melanoma cell behaviors via the miR-215-5p/YY1 axis, which might provide a novel insight for the treatment of melanoma patients.

lncRNA NEAT1 facilitates melanoma cell proliferation, migration, and invasion via regulating miR-495-3p and E2F3

Melanoma contributes a lot to skin cancer-related deaths. lncRNAs are implicated in various diseases, including melanoma. lncRNA NEAT1 is frequently dysregulated and can play important roles in multiple cancers. Nevertheless, little has been studied about the function of NEAT1 in melanoma progression. In our present research, we displayed NEAT1 was overexpressed in melanoma cells. A series of functional assays showed that overexpression of NEAT1 promoted the proliferation, migration, and invasion of melanoma cells. By contrast, NEAT1 knockdown obviously restrained melanoma cell progression. Mechanistically, it was revealed that NEAT1 could directly bind with miR-495-3p, which led to a negative effect on miR-495-3p levels. In addition, miR-495-3p was significantly decreased in melanoma cells. Furthermore, E2F3 was postulated as the target of miR-495-3p and overexpression of this miR could suppress the levels of E2F3. Meanwhile, it was exhibited that melanoma cell proliferation, migration, and invasion induced by E2F3 silence was abrogated by miR-495-3p. Moreover, an in vivo xenograft nude mice model was established using A375 cells and it was indicated that NEAT1 promoted melanoma progression in vivo via regulating the miR-495-3p/E2F3 axis. In conclusion, we suggest that NEAT1 exerts an oncogenic effect on melanoma development via inhibition of miR-495-3p and induction of E2F3. NEAT1 might serve as a crucial prognostic biomarker of melanoma.

Long noncoding RNA HEIH promotes melanoma cell proliferation, migration and invasion via inhibition of miR-200b/a/429

Long noncoding RNAs (lncRNAs) are frequently dysregulated and have important roles in many diseases, particularly cancers. lncRNA-HEIH was first identified in hepatocellular carcinoma (HCC). The expression, clinical significance and roles of lncRNA-HEIH in melanoma are still unknown. In the present study, we found that lncRNA-HEIH is highly expressed in melanoma tissues and cell lines, associated with advanced clinical stages, and predicts poor outcomes in melanoma patients. Functional assays showed that ectopic expression of lncRNA-HEIH promotes melanoma cell proliferation, migration and invasion. Knockdown of lncRNA-HEIH inhibits melanoma cell proliferation, migration and invasion. Mechanistically, we revealed that lncRNA-HEIH directly binds to miR-200b/a/429 promoter and represses miR-200b/a/429 transcription. The expression of miR-200b is inversely associated with lncRNA-HEIH in melanoma tissues. Furthermore, overexpression of miR-200b/a/429 abrogates melanoma cell proliferation, migration and invasion enhanced by lncRNA-HEIH. In conclusion, we identified lncRNA-HEIH as a key oncogene in melanoma via transcriptional inhibition of miR-200b/a/429. Our data suggested that lncRNA-HEIH may serve as a promising prognostic biomarker and therapeutic target for melanoma.

Function and Clinical Implications of Long Non-Coding RNAs in Melanoma

Metastatic melanoma is the most deadly type of skin cancer. Despite the success of immunotherapy and targeted agents, the majority of patients experience disease recurrence upon treatment and die due to their disease. Long non-coding RNAs (lncRNAs) are a new subclass of non-protein coding RNAs involved in (epigenetic) regulation of cell growth, invasion, and other important cellular functions. Consequently, recent research activities focused on the discovery of these lncRNAs in a broad spectrum of human diseases, especially cancer. Additional efforts have been undertaken to dissect the underlying molecular mechanisms employed by lncRNAs. In this review, we will summarize the growing evidence of deregulated lncRNA expression in melanoma, which is linked to tumor growth and progression. Moreover, we will highlight specific molecular pathways and modes of action for some well-studied lncRNAs and discuss their potential clinical implications.