Conjunctival malignant melanoma in Denmark: epidemiology, treatment and prognosis with special emphasis on tumorigenesis and genetic profile

The Epidemiology and Survival Outcomes of Adult Conjunctival Malignancies in Germany: A Decade-Long Population-Based Analysis (2009-2019)

PURPOSE

This study aims to evaluate the epidemiological patterns, treatment strategies, and survival outcomes of conjunctival malignancies in Germany between 2009 and 2019.

METHODS

A total of 1,532 cases were analyzed, with the crude incidence rate calculated. The survival rates were investigated using life tables and Cox regression analysis.

RESULTS

The overall incidence rate was 1.7 per million. Incidence rates varied across age groups, peaking in the 75+ age group. Carcinomas (43%), melanomas (30%), and lymphomas (20%), were the most prevalent malignancies. Of the total cases with reported treatment, surgical intervention was undertaken in 64.5% of the patients. The 5-year overall survival rates were 90.4% for lymphomas, 73.8% for melanomas, and 72.9% for carcinomas. Age at diagnosis emerged as a significant prognostic factor in the Cox regression analysis.

CONCLUSIONS

This study provides the first population-based incidence data on conjunctival malignancies in Germany, noting a generally low incidence with survival rates comparable to other regions. The findings underscore the importance of consistent reporting and further research into risk factors for a deeper understanding of these malignancies. The study calls for improved reporting systems and further investigations into genetic factors and targeted prevention strategies for high-risk groups.

Factors affecting recurrence and metastasis in conjunctival melanoma

PURPOSE

To evaluate clinical and demographic characteristics and factors affecting recurrence, metastasis, and survival in conjunctival melanoma (CM).

METHODS

The clinical records of 45 patients who were treated for CM between October 1998 and June 2022 were retrospectively evaluated. Age, gender, presence of underlying conjunctival nevus-primary acquired melanosis (PAM), tumor stage according to the 8th edition of the American Joint Committee on Cancer (AJCC) staging system, tumor basal diameter, tumor thickness, lymph node (LN) involvement, metastasis, presence of tumor at the surgical margin, treatment method, need for adjuvant therapy, local tumor control, recurrence, and survival were recorded.

RESULTS

Twenty-one (46.7%) patients were female and 24 (53.3%) patients were male. The mean age at diagnosis was 53.2 ± 16.1 years. Median follow up time was 12 (1-300) months. Fifteen (33.3%) patients had conjunctival PAM; 2 (4.4%) patients had conjunctival nevus. The tumor stage was T1 in 24 (55.8%), T2 in 13 (30.2%), and T3 in 6 (14.0%) of the cases. The T stage in 2 cases could not be determined. For stage T1 and T2 CM, in addition to excisional biopsy (EB) and cryotherapy, alcohol epitheliectomy (AE) was performed in 17 cases (37.8%), superficial sclerectomy (SS) was performed in 7 (15.6%), and amnion membrane transplantation (AMT) due to a large conjunctival defect in 9 (20.0%). Six (14.0%) T3 cases underwent primary exenteration. Positive surgical margins were observed in 23 (51.1%) of the excised tumors at histopathologic examination. Adjuvant topical mitomycin-C (MMC) was used in 7 (30.4%) and strontium-90 episcleral brachytherapy in 4 (17.4%) of the 23 cases with tumor-positive borders. During the follow-up, recurrence was seen in 14 (31.1%) cases. According to Kaplan Meier analysis, the mean time to recurrence development was 90.5 ± 16.1 months and the 5-year recurrence free rate was 52.0%. Fourteen of the recurrent cases underwent EB + cryotherapy, 3 underwent AE + SS, and 3 underwent secondary exenteration. Metastasis and LN involvement occurred in 11 (24.4%) and 8 (17.8%) of the cases, respectively. Four (8.9%) cases expired during follow-up. According to Kaplan-Meier analysis, the mean time to metastasis was 106.2 ± 17.3 months and the 5-year metastasis free rate was 52.0%. While recurrence was more frequent in CM developing from PAM/nevus, metastasis was more frequent in men and those with LN involvement.

CONCLUSION

Conjunctival melanoma was a malignant tumor with high recurrence and metastasis rates. Precursor nevus/PAM is a risk factor for recurrence, while male gender and regional LN involvement were risk factors for metastasis in this study.

Giant conjunctival melanoma treated with excision and primary reconstruction using a partial thickness skin graft

Conjunctival melanoma is a rare type of malignancy of ocular surface tissue with a high recurrence rate, sight, and life-threatening malignancy. In this paper, we report a case of giant conjunctival melanoma in an 86-year-old woman, localized on her left eye. The pigmented tumor lesion was de novo occurred and treated by local wide excision and reconstruction of the presented defect by partial thickness skin from the inside parts of the forearm. The eye itself was not damaged, and the first-line lymph nodes showed no malignant activity. In the three years of follow-up, no signs of recurrence have been observed. The treatment approach with local excision and subsequent reconstruction with the partial thickness skin graft or excision with adjuvant therapy has given a good clinical outcome.

Role of MicroRNA-502-3p in Human Diseases

MicroRNAs (miRNAs) are non-coding RNAs that play a major role in gene regulation in several diseases. MicroRNA-502-3p (MiR-502-3p) has been previously characterized in a variety of human diseases such as osteoporosis, diabetes, tuberculosis, cancers, and neurological disorders. Our studies recently explored the new role of miR-502-3p in regulating synapse function in Alzheimer’s disease (AD). AD is the most common cause of dementia in elderly individuals. Synapse is the initial target that is hit during AD progression. The most common causes of synapse dysfunction in AD are amyloid beta, hyperphosphorylated tau, and microglia activation. MiR-502-3p was found to be localized and overexpressed in the AD synapses. Overexpression of miR-502-3p was correlated with AD severity in terms of Braak stages. Studies have shown that miR-502-3p modulates the glutaminergic and GABAergic synapse function in AD. The current study’s emphasis is to discuss the in-depth roles of miR-502-3p in human diseases and AD and the future possibilities concerning miR-502-3p as a therapeutic for AD treatment.

TFOS lifestyle: Impact of societal challenges on the ocular surface

Societal factors associated with ocular surface diseases were mapped using a framework to characterize the relationship between the individual, their health and environment. The impact of the COVID-19 pandemic and mitigating factors on ocular surface diseases were considered in a systematic review. Age and sex effects were generally well-characterized for inflammatory, infectious, autoimmune and trauma-related conditions. Sex and gender, through biological, socio-economic, and cultural factors impact the prevalence and severity of disease, access to, and use of, care. Genetic factors, race, smoking and co-morbidities are generally well characterized, with interdependencies with geographical, employment and socioeconomic factors. Living and working conditions include employment, education, water and sanitation, poverty and socioeconomic class. Employment type and hobbies are associated with eye trauma and burns. Regional, global socio-economic, cultural and environmental conditions, include remoteness, geography, seasonality, availability of and access to services. Violence associated with war, acid attacks and domestic violence are associated with traumatic injuries. The impacts of conflict, pandemic and climate are exacerbated by decreased food security, access to health services and workers. Digital technology can impact diseases through physical and mental health effects and access to health information and services. The COVID-19 pandemic and related mitigating strategies are mostly associated with an increased risk of developing new or worsening existing ocular surface diseases. Societal factors impact the type and severity of ocular surface diseases, although there is considerable interdependence between factors. The overlay of the digital environment, natural disasters, conflict and the pandemic have modified access to services in some regions.

Advances in conjunctival melanoma: clinical features, diagnostic modalities, staging, genetic markers, and management

Conjunctival melanoma, a rare malignancy of the ocular surface, is increasing in incidence. When small, straightforward excision with "no touch" surgery and cryotherapy at an experienced centre can provide excellent outcomes. When advanced, management is more complex and highly individualized. The risk of metastatic disease from conjunctival melanoma is as high as 30% and depends on tumour origin, American Joint Committee on Cancer (AJCC) classification, biomarkers, and perhaps most important, management technique. Metastatic disease can result in melanoma-associated death. Therefore, early detection and prompt directed treatment at an experienced centre are important for protection from metastasis. In this review, we provide an update on conjunctival melanoma clinical features, diagnostic modalities, AJCC staging, genetic markers, and the most critical, controlled management with minimization of tumour seeding. We detail the new era of characterization of conjunctival melanoma with molecular biomarkers that predict melanoma prognosis. This could lead to precision medicine with targeted approaches to specific mutations that improve patient survival. As we work together, the field of conjunctival melanoma is moving forward.

Conjunctival amelanotic melanoma presenting as a multifocal pink lesion

Conjunctival amelanotic malignant melanoma is a rare form of melanoma, which lacks visible pigment and is commonly located underneath the eyelids in the bulbar conjunctiva. In this report, we described a case of a Caucasian women in her 70s who presented with unilateral irritation and tenderness following cataract surgery. On eversion of the eyelid, two elevated pink lesions were noted. Tumour - Node - Metastasis staging with the American Joint Committee on Cancer staging system eighth edition was T3C and required multiple excisions and reconstruction procedures. This case exemplified the diagnostic pitfall of conjunctival amelanotic malignant melanoma, which is a potentially life-threatening disease and the importance of histopathology in the diagnostic process.

Publication trends of research on conjunctival melanoma during 1997–2022: A 25-year bibliometric study

Background

Conjunctival melanoma (CM) is a life-threatening ocular tumor with a high rate of local recurrence and metastasis. Our objective is to analyze research trends in CM field and compare contributions from different countries, institutions and authors.

Methods

We extracted all CM-related publications published from 1997 to 2022 from the Web of Science database and applied Microsoft Excel and VOSviewer to review publication data, analyze publication trends, and visualize relevant data.

Results

A total of 708 publications were identified. The United States contributed the most publications (280) and citations (8,781 times) with the highest H-index value (47). The Ophthalmic Plastic and Reconstructive Surgery, British Journal of Ophthalmology, American Journal of Ophthalmology and Cornea were the most productive journal concerning CM, and Shields CL, Shields JA, Jager MJ as well as Finger PT had published the most papers in the field. Keywords were classified into three clusters: clinical research, management-related research and genetic research. The keywords “primary acquired melanosis”, “metastasis” and “BRAF mutations” were most frequently emerged. According to the average appearing year (AAY), targeted therapy (AAY of 2019.0) and nivolumab (AAY of 2018.7) were identified as the main focuses of the field in the near future.

Conclusion

In the past 25 years, the United States, Germany, England and the Netherlands held the leading position in the CM research. A group of scholars made important contributions to CM research and will continue to guide cutting-edge research. Treatments that have been shown to be effective for advanced cutaneous melanoma, such as targeted therapy and immunotherapy, are potential focuses for future CM research.

Identification of New Vulnerabilities in Conjunctival Melanoma Using Image-Based High Content Drug Screening

Recent evidence suggests that numerous similarities exist between the genomic landscapes of both conjunctival and cutaneous melanoma. Since alterations of several components of the MAP kinases, PI3K/mTOR, and cell cycle pathways have been reported in conjunctival melanoma, we decided to assess the sensitivity of conjunctival melanoma to targeted inhibition mostly of kinase inhibitors. A high content drug screening assay based on automated fluorescence microscopy was performed in three conjunctival melanoma cell lines with different genomic backgrounds with 489 kinase inhibitors and 53 other inhibitors. IC50 and apoptosis induction were respectively assessed for 53 and 48 compounds. The genomic background influenced the response to MAK and PI3K/mTOR inhibition, more specifically cell lines with BRAF V600E mutations were more sensitive to BRAF/MEK inhibition, while CRMM2 bearing the NRASQ61L mutation was more sensitive to PI3k/mTOR inhibition. All cell lines demonstrated sensitivity to cell cycle inhibition, being more pronounced in CRMM2, especially with polo-like inhibitors. Our data also revealed new vulnerabilities to Hsp90 and Src inhibition. This study demonstrates that the genomic background partially influences the response to targeted therapy and uncovers a large panel of potential vulnerabilities in conjunctival melanoma that may expand available options for the management of this tumor.

The m6A reading protein YTHDF3 potentiates tumorigenicity of cancer stem-like cells in ocular melanoma through facilitating CTNNB1 translation

N⁶-methyladenosine (m⁶A) is the most universal internal RNA modification on messenger RNAs and regulates the fate and functions of m⁶A-modified transcripts through m⁶A-specific binding proteins. Nevertheless, the functional role and potential mechanism of the m⁶A reading proteins in ocular melanoma tumorigenicity, especially cancer stem-like cell (CSC) properties, remain to be elucidated. Herein, we demonstrated that the m⁶A reading protein YTHDF3 promotes the translation of the target transcript CTNNB1, contributing to ocular melanoma propagation and migration through m⁶A methylation. YTHDF3 is highly expressed in ocular melanoma stem-like cells and abundantly enriched in ocular melanoma tissues, which is related to poor clinical prognosis. Moreover, YTHDF3 is required for the maintenance of CSC properties and tumor initiation capacity in ocular melanoma both in vitro and in vivo. Ocular melanoma cells with targeted YTHDF3 knockdown exhibited inhibitory tumor proliferation and migration abilities. Transcriptome-wide mapping of m⁶A peaks and YTHDF3 binding peaks on mRNAs revealed a key target gene candidate, CTNNB1. Mechanistically, YTHDF3 enhances CTNNB1 translation through recognizing and binding the m⁶A peaks on CTNNB1 mRNA.

miR-30d-5p: A Non-Coding RNA With Potential Diagnostic, Prognostic and Therapeutic Applications

Cancer is a great challenge facing global public health. Scholars have made plentiful efforts in the research of cancer therapy, but the results are still not satisfactory. In relevant literature, the role of miRNA in cancer has been widely concerned. MicroRNAs (miRNAs) are a non-coding, endogenous, single-stranded RNAs that regulate a variety of biological functions. The abnormal level of miR-30d-5p, a type of miRNAs, has been associated with various human tumor types, including lung cancer, colorectal cancer, esophageal cancer, prostate cancer, liver cancer, cervical cancer, breast cancer and other types of human tumors. This reflects the vital function of miR-30d-5p in tumor prognosis. miR-30d-5p can be identified either as an inhibitor hindering the development of, or a promoter accelerating the occurrence of tumors. In addition, the role of miR-30d-5p in cell proliferation, motility, apoptosis, autophagy, tumorigenesis, and chemoresistance are also noteworthy. The multiple roles of miR-30d-5p in human cancer suggest that it has broad feasibility as a biomarker and therapeutic target. This review describes the connection between miR-30d-5p and the clinical indications of tumors, and summarizes the mechanisms by which miR-30d-5p mediates cancer progression.

New Therapeutic Approaches for Conjunctival Melanoma-What We Know So Far and Where Therapy Is Potentially Heading: Focus on Lymphatic Vessels and Dendritic Cells

Conjunctival melanoma (CM) accounts for 5% of all ocular melanomas and arises from malignantly transformed melanocytes in the conjunctival epithelium. Current therapies using surgical excision in combination with chemo- or cryotherapy still have high rates for recurrences and metastatic disease. Lately, novel signal transduction-targeted and immune checkpoint inhibitors like cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitors, programmed cell death protein-1 (PD-1) receptor inhibitors, BRAF- or MEK-inhibitors for systemic treatment of melanoma have improved the outcome even for unresectable cutaneous melanoma, improving patient survival dramatically. The use of these therapies is now also recommended for CM; however, the immunological background of CM is barely known, underlining the need for research to better understand the immunological basics when treating CM patients with immunomodulatory therapies. Immune checkpoint inhibitors activate tumor defense by interrupting inhibitory interactions between tumor cells and T lymphocytes at the so-called checkpoints. The tumor cells exploit these inhibitory targets on T-cells that are usually used by dendritic cells (DCs). DCs are antigen-presenting cells at the forefront of immune response induction. They contribute to immune tolerance and immune defense but in the case of tumor development, immune tolerance is often prevalent. Enhancing the immune response via DCs, interfering with the lymphatic pathways during immune cell migration and tumor development and specifically targeting tumor cells is a major therapeutic opportunity for many tumor entities including CM. This review summarizes the current knowledge on the function of lymphatic vessels in tumor growth and immune cell transport and continues to compare DC subsets in CM with related melanomas, such as cutaneous melanoma and mucosal melanoma.

Current Management of Conjunctival Melanoma Part 2: Treatment and Future Directions

Conjunctival melanoma is a rare disease which requires tailored management in most cases. The mainstays of treatment can be classified as surgery, topical chemotherapy, radiotherapy, cryotherapy, and other emerging treatment modalities. Herein we review conventional approaches as well as more recently introduced treatment options, together with advances in molecular biology in this particular disease.

5-Hydroxymethylcytosine Loss in Conjunctival Melanoma

Aims: Conjunctival and cutaneous melanoma partially share similar clinical and molecular backgrounds. As 5-hydroxymethylcytosine (5-hmC) loss has been demonstrated in cutaneous melanoma, we decided to assess if similar changes were occurring in conjunctival melanoma. Methods: 5-methylcytosine (5-mC), 5-hmC and TET2 were respectively identified by immunohistochemistry and RNA ISH in 40 conjunctival nevi and 37 conjunctival melanomas. Clinicopathological correlations were established. Results: 5-mC, TET2 and 5-hmC were respectively identified in 67.5%, 95% and 100% of conjunctival nevi and in 81.1%, 35.1% and 54% of conjunctival melanomas. A significant 5-hmC and TET2 loss was identified in conjunctival melanoma comparing to nevus, as well as a significant correlation between TET2 and 5-hmC expression. In the melanomas, 5-hmC expression was only significantly associated with local lymphatic invasion, but not with other clinicopathological parameters. There was a correlation between TET2 expression and the localization of the tumors. 5-mC expression was not associated with any clinicopathological parameters. Conclusions: We identified a significant 5-hmC loss in conjunctival melanoma similar to cutaneous melanoma. This loss may possibly be attributed to TET2 loss or IDH1 mutations. 5-hmC loss in conjunctival melanoma may help in the differential diagnosis between atypical conjunctival nevus and conjunctival melanoma.

PRAME immunohistochemistry is useful in the evaluation of conjunctival melanomas, nevi, and primary acquired melanosis

BACKGROUND

Many dermatopathologists find conjunctival melanocytic proliferations challenging because they are rare relative to their cutaneous counterparts and have nuanced morphology and nomenclature. PRAME immunohistochemistry has been widely adopted for distinguishing cutaneous nevi from melanoma, but limited data exist assessing its utility in evaluating conjunctival specimens. In particular, it is uncertain whether it can predict the risk of melanoma progression in primary acquired melanosis (PAM).

METHODS

Thirty clinically annotated cases (two melanomas, three PAM with atypia, seven PAM without atypia, 15 nevi, two combined nevi, and a diagnostically challenging nevus with atypical features) were retrospectively evaluated with PRAME.

RESULTS

Strong, diffuse PRAME expression was present in melanomas and PAM with high-grade atypia, but not in PAM with low-grade atypia, PAM without atypia, or nevi. Scattered, faintly PRAME-positive intraepithelial melanocyte nuclei were identified in six nevi. A clonal nevus and nests of heavily pigmented type-A melanocytes in two additional nevi had cytoplasmic staining.

CONCLUSIONS

PRAME was useful for distinguishing melanoma and its probable precursors from benign conjunctival melanocytic proliferations in our cohort. The data alert us to two diagnostic pitfalls in nevi: scattered, PRAME-positive intraepithelial melanocytes and cytoplasmic PRAME staining in type-A melanocytes and melanophages. Larger scale investigations are warranted to further substantiate these promising findings.

lncRNA NEAT1 regulates gastric carcinoma cell proliferation, invasion and apoptosis via the miR‑500a‑3p/XBP‑1 axis

Gastric cancer is a serious malignant tumor. Despite progression in gastric cancer research in recent years, the specific molecular mechanism underlying the pathogenesis of the disease is not completely understood. Long non-coding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (NEAT1) affects the proliferation and metastasis of multiple types of tumor cells in colorectal cancer and breast cancer but its specific role in gastric cancer requires further investigation. The aim of the present study was to analyze the role of NEAT1 in gastric cancer. The expression of endoplasmic reticulum stress marker proteins and apoptosis-related proteins in gastric cancer tissue and cell lines was analyzed using western blotting. The targeting relationship of NEAT1 and miR-500a-3p was analyzed using dual-luciferase reporter assay. Cell proliferation was analyzed using CCK8 assay and colony formation assay while cell invasion was detected using Transwell assay. Cell apoptosis was analyzed using TUNEL staining and LC3 expression through immunofluorescent staining (IF). The results showed that lncRNA NEAT1-overexpression gastric cancer cells were established to determine its effects on cell proliferation, invasion, apoptosis, autophagy and endoplasmic reticulum stress. Subsequently, microRNA (miR)-500a was overexpressed in lncRNA NEAT1-overexpression cells. Compared with the vector group, lncRNA NEAT1 overexpression significantly inhibited gastric cancer cell proliferation and invasion, but significantly promoted cell apoptosis. Furthermore, the results indicated that lncRNA NEAT1 targeted and downregulated the expression of miR-500a-3p, and miR-500a-3p targeted X-box binding protein-1 (XBP-1) mRNA. lncRNA NEAT1 overexpression-mediated inhibition of gastric cancer cell proliferation and invasion was significantly reversed by miR-500a-3p overexpression. Furthermore, compared with the vector group, the expression levels of endoplasmic reticulum stress-related proteins (XBP-1S/XBP-1U ratio and 78-kDa glucose-regulated protein) and apoptosis-related proteins (Bax and cleaved-caspase-3) were significantly upregulated by lncRNA NEAT1 overexpression; however, miR-500a-3p overexpression reversed lncRNA NEAT1 overexpression-mediated effects on protein expression. The present study demonstrated that lncRNA NEAT1 inhibited gastric cancer cell proliferation and invasion, and promoted apoptosis by regulating the miR-500a-3p/XBP-1 axis.

MicroRNAs expression associated with aggressive clinicopathological features and poor prognosis in primary cutaneous melanomas

Several studies have focused on identifying microRNAs involved in the pathogenesis of melanoma. However, its association with clinicopathological features has been scarcely addressed. The aim of this study is to identify microRNAs expression profiles related to aggressive clinicopathological and molecular features, and to analyze the association with melanoma survival. A retrospective and observational study was performed in a series of 179 formalin-fixed paraffin embedded primary cutaneous melanomas. First, a screening analysis on a discovery set (n = 22) using miRNA gene chip array (Affymetrix, Santa Clara, California, USA) was performed. Differentially expressed microRNAs were detected employing the software Partek Genomic Suite. Validation of four microRNAs was subsequently performed in the entire series (n = 179) by quantitative real time PCR (qRT-PCR). MicroRNAs expression screening analysis identified 101 microRNAs differentially expressed according to Breslow thickness (≤1 mm vs. >1 mm), 79 according to the presence or absence of ulceration, 78 according to mitosis/mm2 (<1 mitosis vs. ≥1 mitosis) and 97 according to the TERT promoter status (wt vs. mutated). Six microRNAs (miR-138-5p, miR-130b-3p, miR-30b-5p, miR-34a-5p, miR-500a-5p, miR-339-5p) were selected for being validated by qRT-PCR in the discovery set (n = 22). Of those, miR-138-5p, miR-130b-3p, miR-30b-5p, miR-34a-5p were selected for further analysis in the entire series (n = 179). Overexpression of miR-138-5p and miR-130b-3p was significantly associated with greater Breslow thickness, ulceration, and mitosis. TERT mutated melanomas overexpressed miR-138-5p. Kaplan-Meier survival analysis showed poorer survival in melanomas with miR-130b-3p overexpression. Our findings provide support for the existence of a microRNA expression profile in melanomas with aggressive clinicopathological features and poor prognosis.

MiR-501-3p promotes osteosarcoma cell proliferation, migration and invasion by targeting BCL7A

Increasing numbers of evidences have demonstrated that microRNAs (miRNAs) play an important role in osteosarcoma (OS) cell functions. MiR-501-3p has been reported to play an important role in several types of tumors, including prostate cancer and hepatocellular carcinoma. However, the biological function and potential mechanism of miR-501-3p in OS have not been well investigated until now. Here, we analyzed the expression of miR-501-3p in OS tissues and cell lines and its clinical significance in OS patients. Quantitative reverse transcription PCR showed miR-501-3p was significantly up-regulated in OS tissues and cell lines. Up-regulated miR-501-3p expression was associated with TNM stage, distal metastasis and worse prognosis in OS patients. MiR-501-3p knockdown and overexpression were achieved by miR-501-3p inhibitor and mimics transfection, respectively. CCK-8, colony formation and transwell assays showed that miR-501-3p knockdown in U2OS and Saos-2 cells suppressed, while miR-501-3p overexpression in Saos-2 cells promoted cell proliferation, migration and invasion. Moreover, luciferase reporter assay supporting BCL7A was a target of miR-501-3p and its expression was increased by miR-501-3p inhibitor, but inhibited by miR-501-3p mimics. By performing rescue experiments, we further demonstrated that BCL7A was a downstream functional regulator involved in miR-501-3p promoting OS cell functions. In summary, our findings suggest that miR-501-3p targets BCL7A may provide novel therapeutic targets for the treatment of OS.

Current Management of Conjunctival Melanoma Part 1: Clinical Features, Diagnosis and Histopathology

Conjunctival melanoma is a rare disease which makes up approximately 5% of ocular melanomas. The lesion may occur de novo or originate from a pre-existing nevus or primary acquired melanosis. Biomicroscopy is of paramount importance in diagnosis and follow-up of the disease, while other diagnostic modalities serve as supplementary tools. Many clinical and histopathological risk factors have been reported for prognosis. This review aims to address the clinical findings, differential diagnosis, diagnostic tools, prognostic factors, and staging of this disease.

Clinical treatment options for early-stage and advanced conjunctival melanoma

Conjunctival melanoma (CM) is an ocular malignant tumor arising from the bulbar and palpebral conjunctiva and from the caruncle. The treatment of early-stage CM is wide local excision, followed by cryotherapy to the margins and adjuvant therapy postoperatively. Advanced CM has a poor prognosis, and there is no consensus on its management. With the development of precision medicine, the identification of genetic alterations assumes great importance. The genetic characteristics of CM, such as BRAF, NRAS, and NF1 mutations, may provide potential therapeutic targets. For locally advanced tumors and metastatic disease, targeted therapy such as BRAF inhibitors and MEK inhibitors in vitro show therapeutic benefit. Some individual case reports indicate their potential effectiveness in advanced CM. In addition, immune checkpoint inhibitors, such as programmed cell death-1 and cytotoxic T lymphocyte antigen-4 inhibitors, have been successfully used for advanced cutaneous melanoma and may be effective in CM. Limited clinical case reports found immune checkpoint inhibitors effective in advanced CM. More clinical studies are needed.

TLD1433 Photosensitizer Inhibits Conjunctival Melanoma Cells in Zebrafish Ectopic and Orthotopic Tumour Models

The ruthenium-based photosensitizer (PS) TLD1433 has completed a phase I clinical trial for photodynamic therapy (PDT) treatment of bladder cancer. Here, we investigated a possible repurposing of this drug for treatment of conjunctival melanoma (CM). CM is a rare but often deadly ocular cancer. The efficacy of TLD1433 was tested on several cell lines from CM (CRMM1, CRMM2 and CM2005), uveal melanoma (OMM1, OMM2.5, MEL270), epidermoid carcinoma (A431) and cutaneous melanoma (A375). Using 15 min green light irradiation (21 mW/cm², 19 J.cm^-2, 520 nm), the highest phototherapeutic index (PI) was reached in CM cells, with cell death occurring via apoptosis and necrosis. The therapeutic potential of TLD1433 was hence further validated in zebrafish ectopic and newly-developed orthotopic CM models. Fluorescent CRMM1 and CRMM2 cells were injected into the circulation of zebrafish (ectopic model) or behind the eye (orthotopic model) and 24 h later, the engrafted embryos were treated with the maximally-tolerated dose of TLD1433. The drug was administrated in three ways, either by (i) incubating the fish in drug-containing water (WA), or (ii) injecting the drug intravenously into the fish (IV), or (iii) injecting the drug retro-orbitally (RO) into the fish. Optimally, four consecutive PDT treatments were performed on engrafted embryos using 60 min drug-to-light intervals and 90 min green light irradiation (21 mW/cm², 114 J.cm^-2, 520 nm). This PDT protocol was not toxic to the fish. In the ectopic tumour model, both systemic administration by IV injection and RO injection of TLD1433 significantly inhibited growth of engrafted CRMM1 and CRMM2 cells. However, in the orthotopic model, tumour growth was only attenuated by localized RO injection of TLD1433. These data unequivocally prove that the zebrafish provides a fast vertebrate cancer model that can be used to test the administration regimen, host toxicity and anti-cancer efficacy of PDT drugs against CM. Based on our results, we suggest repurposing of TLD1433 for treatment of incurable CM and further testing in alternative pre-clinical models.

Circulating microRNAs as biomarkers for early diagnosis of cutaneous melanoma

Introduction: Cutaneous melanoma is the deadliest form of skin cancer, with a dramatic increase in the incidence rate worldwide over the past decade. Early detection has been shown to improve the outcome of melanoma patients. The identification of noninvasive biomarkers able to identify melanoma at an early stage remains an unmet clinical need. Circulating miRNAs (c-miRNAs), small non-coding RNAs, appear as potential ideal candidate biomarkers due to their stability in biological fluids and easy detectability. Moreover, c-miRNAs are reported to be heavily deregulated in cancer patients.Areas covered: This review examines evidence of the specific c-miRNAs or panels of c-miRNAs reported to be useful in discriminating melanoma from benign cutaneous lesions.Expert opinion: Although the interesting reported by published studies, the non-homogeneity of detection and normalization methods prevents the individuation of single c-miRNA or panel of c-miRNAs that are specific for early detection of cutaneous melanoma. In the future, prospective wide and well-designed clinical trials will be needed to validate the diagnostic potential of some of the c-miRNA candidates in clinical practice.

A novel KRAS mutation in metastasic conjunctival melanoma: a case report and literature review

Conjunctival melanoma is a rare disease, and little is known about its molecular background. Here, we present the case of a 48-year-old patient with conjunctival melanoma and metachronic lymph node and skin metastasis with KRAS p.K117Y mutation in exon 4 in all the lesions. The cancer genome interpreter predicted this mutation to have driver function. To our knowledge, this is the first time this mutation is found in conjunctival melanoma. An important role in the disease development is suggested.

MicroRNA-501-3p restricts prostate cancer growth through regulating cell cycle-related and expression-elevated protein in tumor/cyclin D1 signaling

MicroRNA-501-3p (miR-501-3p) has been reported as a novel cancer-related miRNA in many types of cancer. However, the precise biological function of miR-501-3p in prostate cancer remains unknown. In this study, we aimed to investigate the regulatory effect and mechanism of miR-501-3p on cell growth of prostate cancer cells. We found that miR-501-3p expression was significantly downregulated in prostate cancer tissues and cell lines. Gain-of-function experiments showed that upregulation of miR-501-3p expression significantly decreased cell proliferation and colony formation, and induced cell cycle arrest in the G0/G1 phase. Bioinformatics analysis predicted that cell cycle-related and expression-elevated protein in tumor (CREPT) was a potential target gene of miR-501-3p., and the results of our luciferase reporter assay confirmed that miR-501-3p bound to the 3'-untranslated region of CREPT at the predicted binding site. Moreover, miR-501-3p was shown to negatively regulate CREPT expression in prostate cancer cells. Correlation analysis showed that miR-501-3p was inversely correlated with CREPT expression in prostate cancer tissues. Knockdown studies revealed that miR-501-3p regulated the expression of cyclin D1 by targeting CREPT. Additionally, the inhibitory effect of miR-501-3p on prostate cancer cell growth was partially reversed by CREPT overexpression. Overall, these results suggest that miR-501-3p restricts prostate cancer cell growth by targeting CREPT to inhibit the expression of cyclin D1. These findings indicate that the miR-501-3p/CREPT/cyclin D1 axis plays a crucial role in the progression of prostate cancer and may serve as potential therapeutic target.

[Focus on clinical and pathological management of conjunctival melanocytic tumors]

Conjunctival-pigmented tumors are rare, but they are one of the most commonly encountered by the pathologist working with the department of ophthalmology. Nevus and melanoma can be encountered and have some histological difference compared to their cutaneous counterpart. Primary acquired melanosis (PAM) is a conjunctival specific entity. This clinical term includes several histological lesions ranging from benignity to melanoma precursor lesion. Histologic examination determines the therapy and the risk of progression to melanoma. We present here a histopathological, clinical and therapeutic synthesis of conjunctival-pigmented lesions, emphasizing the importance of a good understanding between clinicians and pathologists.

Conjunctival Melanoma - Epidemiological Trends and Features

Conjunctival melanoma is a rare but sight and life threatening malignancy. It accounts for 2%-5% of all ocular tumours and 5%-7% of all ocular melanomas with an incidence of 0.2-0.8 per million in the Caucasian population with rare cases reported in the non-Caucasians. In recent decades the incidence of uveal melanoma has been relatively stable whilst conjunctival and cutaneous melanoma have shown increasing incidence which may be connected to the result of environmental exposure to ultraviolet light. The dissimilarity in incidence between light and dark pigmented individuals observed in conjunctival melanomas compared to uveal and cutaneous melanomas may be related to differences in their histological structures and genetic profile. Recent molecular biological studies support the fact that each type of melanoma undergoes its own molecular changes and has characteristic biological behaviour. Further studies are required for each type of melanoma in order to ascertain their individual etiology and pathogenesis and based on this knowledge develop relevant preventative and treatment procedures.

Population-based incidence of conjunctival tumours in Olmsted County, Minnesota

AIM

To determine population-based incidence of conjunctival tumours in Olmsted County, Minnesota.

METHODS

The Rochester Epidemiology Project medical record linkage system was used to identify patients with conjunctival tumours in Olmsted County (1 January 1980 to 31 December 2015). Records were reviewed for demographics, types of tumours, histopathology, treatment and clinical course. Incidence rate of all tumours was calculated per 1 000 000 person-years. Poisson regression analysis was used to assess changes in incidence over time.

RESULTS

There were 504 patients with conjunctival tumours, giving an age-adjusted and sex-adjusted incidence rate of 125 per 1 000 000 (CI 113.5 to 135.5). Incidence increased over time (P<0.001). Most tumours (474, 94%) were benign. Of benign lesions, melanocytic lesions accounted for the majority (431, 86%), with adjusted incidence rates of 10.8 (CI 7.7 to 13.9) for complexion-associated melanosis, 49.7 (CI 42.9 to 56.6) for nevus and 44.1 (37.5-50.8) for primary acquired melanosis. Malignant lesions were rare (30, 6%) with 6 cases of melanoma, 21 cases of ocular surface squamous neoplasia (OSSN), 1 case of Langerhans cell histiocytosis and 2 cases of lymphoma. Adjusted incidence rates of conjunctival melanoma and OSSN were 1.5 (CI 0.3 to 2.8) and 6.1 (CI 3.5 to 8.7), respectively. Outcomes for melanoma (mean follow-up 14 years, range 0-34) and OSSN (mean follow-up 4 years, range 0-24) were favourable in 29 cases, with one fatality due to metastatic melanoma.

CONCLUSIONS

In a population-based setting, most conjunctival tumours are benign, and the majority of lesions are melanocytic. While it is important to remain vigilant for malignancies, most conjunctival lesions in a community-based practice are not life-threatening.

The prognostic relevance of primary tumor location in patients undergoing resection for pancreatic ductal adenocarcinoma

Different clinical presentations and prognoses have been implied between pancreatic head and body/tail cancers. We aimed to identify the prognostic relevance of primary tumor location in patients undergoing resection for pancreatic ductal adenocarcinoma (PDAC). Thirty-two pairs of patients with strictly matched early stage (II) pancreatic head and body/tail cancers were enrolled. The molecular feature of the two subtypes of PDAC was assessed on the level of miRNA expression. Out of the 64 patients, 34 (53.1%) had tumor recurrence after radical resection during the follow-up period (2.3 ± 0.8 years). Both overall and tumor-free survival were significantly higher in the patients with pancreatic body/tail cancer compared with those with pancreatic head cancer. Patient age and tumor location were the independent prognostic factors for tumor recurrence. A remarkably lower expression of miR-501-3p and higher expression of miR-375 were found and were further verified in pancreatic body/tail cancer tissues compared with pancreatic head cancer tissues. The low expression of miR-501-3p was significantly associated with a low risk of tumor recurrence. Both, subcutaneous and orthotopic PDAC mouse models presented highly invasive tumor phenotypes upon up-regulated miR-501-3p expression. An in vitro study showed that miR-501-3p promoted the invasiveness of PDAC cells possibly via suppressing E-cadherin. In summary, at resectable early stage, pancreatic body/tail cancer presents a less malignant phenotype associated with deregulation of miR-501-3p compared with pancreatic head cancer.

Conjunctival Tumors: Review of Clinical Features, Risks, Biomarkers, and Outcomes--The 2017 J. Donald M. Gass Lecture

Conjunctival tumors encompass a broad range of diagnoses. The 3 most important malignant tumors include ocular surface squamous neoplasia (OSSN) (14%), melanoma (12%), and lymphoma (7%). Conjunctival malignancies are rarely found in children. Regarding OSSN, pre-disposing conditions include chronic solar radiation, immune deficiency (HIV), organ transplant, autoimmune conditions, xeroderma pigmentosum, and chronic exposure to cigarette smoke. OSSN is managed surgically or with topical/injection immunotherapy or chemotherapy. Metastasis occurs in <1%. Regarding melanoma, predisposing conditions include primary acquired melanosis (PAM), chronic nevus, and chronic solar radiation. Treatment of PAM or nevus can prevent melanoma. Melanoma management involves surgical resection with clean margins and avoidance of direct tumor manipulation ("no touch" technique). The first surgery is most important, to minimize tumor seeding. Biomarkers including BRAF, TERT, and PTEN provide information regarding risk for metastasis and allow for targeted antibiomarker therapies. Ten-year risk for melanoma metastasis is 25%. Tumors >2 mm thickness or those located in fornix, caruncle, or orbit are at highest risk for metastasis. Regarding lymphoma, predisposing conditions include benign reactive lymphoid hyperplasia, immune deficiency (HIV), immune dysfunction, and chronic inflammation/infection (Helicobacter pylori, Chlamydia psittaci). The 4 most important subtypes include extranodal marginal zone lymphoma (ENMZL), follicular lymphoma, mantle cell lymphoma (MCL), and diffuse large B-cell lymphoma. Treatment includes surgical resection, cryotherapy, radiotherapy, systemic chemotherapy, or targeted anti-B-cell therapy (rituximab). Lymphoma-related survival (5-year) depends on subtype and ranges from 97% (ENMZL) to 9% (MCL). Recognizing conjunctival tumors and understanding predisposing factors, biomarkers, and treatment strategies are vital to patient outcomes.

Systemic BRAF/MEK Inhibitors as a Potential Treatment Option in Metastatic Conjunctival Melanoma

AIM

In this review, we outline similarities between conjunctival and skin melanoma as well as the effectiveness of combined BRAF/MEK inhibition in melanoma, and discuss the applicability of these agents in conjunctival melanoma.

METHODS

The study provides a PubMed literature review.

RESULTS

Conjunctival melanoma and skin melanoma are genetically and phenotypically related. Both tumors typically harbor BRAF mutations in more than 50% of cases. New targeted therapies in metastatic skin melanoma include selective inhibition of BRAF and MEK. Combined BRAF/MEK inhibition has revolutionized the treatment of metastatic skin melanoma, significantly improving patients' prognoses. While these new substances have been investigated extensively in the treatment of skin melanoma, comparable studies in conjunctival melanoma do not exist owing to the rarity of the malignancy.

CONCLUSIONS

The application of combined BRAF/MEK inhibition in metastatic or unresectable conjunctival melanoma shows great potential for improving patients' prognoses. Future studies are needed to investigate the assumed benefit.