Genomic Evaluation of Clinically Ambiguous Pigmented Lesions

The clinical evaluation of pigmented lesions represents a 'high-stakes' scenario as a missed melanoma can be fatal. Traditional clinical assessment visually sorts pigmented lesions into those that merit a biopsy and those that do not. In our practice there exists a group of lesions judged to not merit biopsy where melanoma, while very unlikely, cannot be excluded with absolute certainty. These ambiguous pigmented lesions (APLs) were often photographed and followed for clinical evolution. This article evaluates the presence of APLs and describes the use of non-invasive genomic testing to sort them. An informal survey using pictures of 10 APLs found that 6 of 8 dermatology providers were unable to identify which were melanomas. Next, our single practice chart review of 1,254 APLs evaluated by non-invasive genomic testing revealed 35 melanomas. All 1,254 were lesions that fell below our biopsy threshold. Non-invasive genomic testing can improve biopsy decisions particularly in clinically indeterminate pigmented lesions.

Dermoscopic features associated with 3-GEP PLA: LINC00518, PRAME, and TERT expression in suspicious pigmented lesions

Utilization of dermoscopy and novel molecular triage technologies augments visual triage of pigmented skin lesions, promoting early detection of melanoma. One emerging in vivo genomic test, 3-GEP pigmented lesion assay (3-GEP PLA) aids in pigmented lesion triage by noninvasively detecting the presence of three genes associated with melanoma: LINC00518, PRAME, and TERT. The purpose of our retrospective case-control study was to identify dermoscopic features uniquely associated with the presence of LINC00518, PRAME, or TERT in the stratum corneum as determined by 3-GEP PLA testing. Images of suspicious pigmented lesions that had undergone 3-GEP PLA testing and received a definitive positive or negative result (n = 393) were evaluated for the presence of specific clinical and dermoscopic features associated with melanoma. We found that asymmetry of color was a significant predictor for PRAME expression (Odds Ratio (OR) 5.5, 95% Confidence Interval (CI) 1.6-34.5, p = 0.004), blue color and negative pigment network were significant predictors for LINC00518 expression (adjusted OR 2.7, 95% CI 1.2-5.5, p = 0.014 and adjusted OR 5.4, 95% CI 1.6-16.9, p = 0.010, respectively), and atypical polymorphous vessels present in a pigmented skin lesion were a significant predictor for TERT promoter mutations (OR 5.8, 95% CI 1.3-23.4, p = 0.022). The results presented suggest a hierarchy in the significance of these dermoscopic features and may help guide evaluation and management of pigmented skin lesions.

ESRG, LINC00518 and PWRN1 are newly-identified deregulated lncRNAs in colorectal cancer

Colorectal cancer is the 2nd leading cause of death in humans because of cancer. This rank of death could be due to the high rate of incidence from one hand, and the lack of sufficient diagnostic and therapeutic approaches from the other hand. Thus, molecular tools have been emerging as the potential biomarker to improve the early diagnosis and therapeutic management that subsequently could lead to the heightened survival rate of colorectal cancer patients. Long non-coding RNA (lncRNAs) have shown promising capabilities to be used in clinics. The profiling methods could identify novel aberrantly expressed lncRNAs in colorectal cancer. We, thus, performed a comprehensive and unbiased approach to shortlist the dysregulated lncRNAs based on the colon adenocarcinoma TCGA data. An unbiased in silico method was used to rank the yet to profiled lncRNAs in colorectal cancer. qPCR was used to measure the expression level of selected lncRNAs. Our results nominated ESRG, LINC00518, PWRN1, and TTTY14 lncRNAs as the top-hit novel lncRNAs with aberrant expression in colon cancer. The qPCR method was used to profile these lncRNAs that showed the up-regulation of ESRG and LINC00518, and down-regulation of TTTY14 in thirty paired colorectal cancer specimens. The statistical analyses demonstrated that ESRG, LINC00518 and PWRN1 could distinguish the tumor from normal samples. Moreover, ESRG showed a negative correlation with the overall survival of patients. These diagnostic and prognostic results suggest that profiling ESRG, LINC00518 and PWRN1 s may have implications in clinics.

LINC00518 Promotes Cell Proliferation by Regulating the Cell Cycle of Lung Adenocarcinoma Through miR-185-3p Targeting MECP2

Previous studies have shown that long intergenic non-protein coding RNA 00518 (LINC00518) are essential for the cell growth and metastasis of human cancer. However, the role of LINC00518 in lung adenocarcinoma (LUAD) is still unknown. This research put emphasis on the function of LINC00518 on the cell growth of LUAD. The lncRNA, miRNA and mRNA expression were measured by using qRT-PCR. Protein levels were measured by using Western blotting. CCK-8, colony formation assays and transwell assay were performed to evaluate the cell proliferation ability and invasion. Bioinformatic analysis and luciferase reporter assays were chosen to confirm the mechanism of LINC00518 in LUAD. We found that LINC00518 was highly expressed in LUAD specimens and the high-expression was negatively correlated with the overall survival rates. This finding was also proved in the LUAD cell lines. Through a series of in vitro and in vivo experiments, we proved that LICN00518 promoted the cell growth of LUAD by regulating the cell cycle. Moreover, LICN00518 upregulated the expression of MECP2 by mutagenesis of miR-185-3p. The results suggested that LICN00518 could be used as a survival indicator and potential therapeutic target for LUAD patients.

LINC00518 Interference Inhibits Non-Small Cell Lung Cancer by Upregulating miR216b-5p Expression

Introduction

Non–small cell lung cancer (NSCLC) accounts for the majority of lung cancer cases, and effective treatment for this disease is still lacking. This study aimed to explore the potential role of LINC00518 and miR216b-5p on cell proliferation and tumor growth in NSCLC.

Methods

The expression of LINC00518, miR216b-5p, MMP7, and MMP9 in NSCLC cell lines was determined by RT-qPCR analysis, which was also used to confirm the transfection effects. After transfection, proliferation, clone-formation ability, migration, and invasion of NSCLC cells were detected by CCK8, clone-formation, wound-healing, and transwell assays, respectively. Western blot analysis was used to detect the expression of MMP7, MMP9, Ki67, and PCNA. A xenograft model was constructed by subcutaneous injection of transfected NSCLC cells into nude mice.

Results

The results indicated that LINC00518 expression was increased and miR216b-5p expression decreased in NSCLC cell lines, and A549 cells were chosen for the next experiments. LINC00518 interference inhibited proliferation, invasion, and migration of A549 cells, together with the progression of NSCLC in vivo. In addition, LINC00518 directly targeted miR216b-5p. Downregulation of miR216b-5p weakened the inhibitory effect of LINC00518 interference on proliferation, invasion, and migration of A549 cells, as well as progression of NSCLC in vivo.

Discussion

In conclusion, LINC00518 interference inhibits NSCLC, which is partially reversed by downregulation of miR216b-5p expression.

Down-regulated expression of LINC00518 prevents epithelial cell growth and metastasis in breast cancer through the inhibition of CDX2 methylation and the Wnt signaling pathway

Breast cancer (BC)-related mortality is associated with the potential metastatic properties of the primary breast tumors. The following study was conducted with the main focus on the effect of LINC00518 on the growth and metastasis of BC epithelial cells via the Wnt signaling pathway through regulation of the methylation of CDX2 gene. Initially, differentially expressed long intergenic non-protein coding RNAs (lincRNAs) related to BC were screened out in the Cancer Genome Atlas (TCGA) database, after which we detected the LINC00518 expression and localization in BC tissues and cells. Then the CDX2 positive expression and methylation level were identified. The targeting relationship of LINC00518 and CDX2, and binding methyltransferase in the promoter region were examined. BC epithelial cell proliferation, colony formation ability, invasion, migration and apoptosis were further evaluated. The lincRNA expression data related to BC downloaded from the TCGA database revealed that there was a high expression of LINC00518 in BC, and a negative correlation between LINC00518 and CDX2. In addition, LINC00518 promotes CDX2 methylation by recruiting DNA methyltransferase through activating the Wnt signaling pathway. The down-regulation of LINC00518 inhibited proliferation, invasion, migration, and EMT of BC epithelial cells while enhancing apoptosis. The inhibitory effects of LINC00518 down-regulation was reversed by CDX2 down-regulation. In conclusion, our findings revealed that down-regulation of LINC00518 might have the ability to suppress BC progression by up-regulating CDX2 expression through the reduction of methylation and blockade of the Wnt signaling pathway, resulting in the inhibition of proliferation and promotion of apoptosis of BC epithelial cells.

Development and validation of a noninvasive 2-gene molecular assay for cutaneous melanoma

Background

Clinical and histopathologic assessment of pigmented skin lesions remains challenging even for experts. Differentiated and accurate noninvasive diagnostic modalities are highly desirable.

Objective

We sought to provide clinicians with such a tool.

Methods

A 2-gene classification method based on LINC00518 and preferentially expressed antigen in melanoma (PRAME) gene expression was evaluated and validated in 555 pigmented lesions (157 training and 398 validation samples) obtained noninvasively via adhesive patch biopsy. Results were compared with standard histopathologic assessment in lesions with a consensus diagnosis among 3 experienced dermatopathologists.

Results

In 398 validation samples (87 melanomas and 311 nonmelanomas), LINC00518 and/or PRAME detection appropriately differentiated melanoma from nonmelanoma samples with a sensitivity of 91% and a specificity of 69%. We established LINC00518 and PRAME in both adhesive patch melanoma samples and underlying formalin fixed paraffin embedded (FFPE) samples of surgically excised primary melanomas and in melanoma lymph node metastases.

Limitations

This technology cannot be used on mucous membranes, palms of hands, and soles of feet.

Conclusions

This noninvasive 2-gene pigmented lesion assay classifies pigmented lesions into melanoma and nonmelanoma groups and may serve as a tool to help with diagnostic challenges that may be inherently linked to the visual image and pattern recognition approach.