Elevated VEGF-A & PLGF concentration in aqueous humor of patients with uveal melanoma following Iodine-125 plaque radiotherapy

Central subfield thickness predicts visual acuity outcomes in plaque-irradiated eyes with choroidal melanoma

OBJECTIVE

To determine the association between pre-operative central subfield thickness (CST) and post-radiotherapy visual acuity (VA), cystoid macular edema (CME), and intravitreal anti-vascular endothelial growth factor (VEGF) requirement.

DESIGN

Single-center retrospective study.

PARTICIPANTS

Patients with plaque-irradiated extramacular choroidal melanoma treated between 11/11/2011 and 4/30/2021. Pre-operative CST difference between the affected and unaffected eye was used. Kaplan-Meier analysis and hazard ratios were calculated.

RESULTS

Of 85 patients, pre-operative CST was greater in the melanoma-affected eye (vs. fellow eye) by mean of 20.4 μm (median 14.0, range - 60.0-182.0). Greater CST at presentation (vs. fellow eye) was associated with larger tumor diameter (p = 0.02), greater tumor thickness (p < 0.001), and more frequent tumor-related Bruch's membrane rupture (p = 0.006). On univariate analysis of outcome data, greater CST at presentation (vs. fellow eye) was associated with higher 5-year risk (1.09 [1.02-1.17], p = 0.02) of VA 20/200 or worse and increased (1.10 [1.01-1.20], p = 0.03) likelihood for anti-VEGF injections after plaque irradiation. There was no significant association with CME. The association between CST and VA outcome remained significant on multivariate analysis accounting for impact of tumor thickness and radiation dose to optic disc, while tumor distance to fovea was the only significant factor on multivariate analysis for anti-VEGF injections.

CONCLUSION

Greater CST at presentation (vs. fellow eye) was associated with worse VA outcome following plaque radiotherapy for choroidal melanoma. Large-sized tumors may contribute to a higher intraocular VEGF burden, potentially leading to greater preoperative CST, which correlates with poor VA outcome post-plaque radiotherapy.

Genetic and Epigenetic Features of Uveal Melanoma-An Overview and Clinical Implications

Uveal melanoma (UM) is rare, but it is the most common primary intraocular malignancy among adults. This review represents the molecular, genetic, and immunobiological mechanisms involved in UM carcinogenesis and progression, as well as data about the association of chromosomal changes, genetic mutations, selective proteins, and biochemical biomarkers with the clinical implications of UM. Genetic analysis has the potential to identify patients with a high risk of UM metastasis, enabling management that is more effective and allowing for the follow-up of patients. Advancements in molecular characterization of UM offer opportunities to develop targeted therapeutic strategies by focusing on relevant signaling pathways. Changes in miRNA expression could be useful in the diagnosis and prognosis of UM, due to unique miRNA profiles in melanoma cells or tissue and its association with metastasis. Although liver function tests do not provide enough data on the prognosis of UM, due to the high frequency of liver metastasis, liver function tests (LFTs) might be useful indicators; however, the absence of rising LFT values cannot lead to the exclusion of liver metastases. Molecular analysis of tumor tissue will allow us to identify patients with the added benefit of new therapeutic agents and provide a better insight into melanoma pathogenesis and its biological behavior.

Utility of isolated-check visual evoked potential technique in dysthyroid optic neuropathy

PURPOSE

To analyze the utility of isolated-check visual evoked potential (icVEP) for discriminating between eyes with dysthyroid optic neuropathy (DON) and eyes with thyroid-associated ophthalmopathy (TAO) but not DON.

METHODS

Forty-three eyes with TAO but not DON (as non-DON), fifty-three eyes with DON, and sixty healthy eyes (as controls) were included. Comprehensive ophthalmic examinations, including best-corrected visual acuity, refraction, color vision test, intraocular pressure measurement, slit-lamp biomicroscopy, ophthalmoscopy, RAPD, exophthalmometry measurements, pVEP test, icVEP test, standard automated perimetry, and clinical activity score classification of TAO, as well as demographic information, were collected and analyzed.

RESULTS

In the DON group, the signal-to-noise ratio (SNR) value of icVEPs decreased significantly compared with that of the non-DON group as well as control (p < 0.05). The SNR values under 8%, 16% and 32% depth of modulation (DOM) were significantly negatively correlated with BCVA (p < 0.05, r =  - 0.9 ~  - 0.6), papilledema (Y/N) (p < 0.05, r =  - 0.8 ~ 0.4) and DON (Y/N) (p < 0.001, r =  - 0.7 ~  - 0.5). The 8% DOM of icVEP had the largest area under the receiver operating characteristic curve (AUC) (0.842) for discriminating DON from non-DONs. Meanwhile, decision curve analysis (DCA) showed that patients clinically benefit most from 8% DOM of icVEP. Furthermore, the 8% DOM of icVEP combing with papilledema (Y/N) and BCVA (Model 1) has significantly larger AUC than the 8% DOM of icVEP (p = 0.0364), and has better clinical benefit in DCA analysis.

CONCLUSIONS

The SNR of 8% DOM from icVEP may represent a significant ancillary diagnostic method for DON detection. Furthermore, icVEP combined with papilledema (Y/N) and BCVA should be considered as a diagnostic model in future clinical practice.

Advances in the treatment of intraocular malignancies: A literature review

Intraocular malignant tumors including primary and metastatic tumors, are mainly found in Retina and uvea, and very few cases originate from the sclera and optic nerve. Intraocular tumors can endanger the patient's vision and even life, and proper treatment is vital. There have been several traditional treatments for intraocular tumors, such as radiotherapy, chemotherapy and surgery. In recent years, new methods have been developed in clinical applications including anti-VEGF and gene therapy. This paper aims to provide a timely review about recent progress in the treatment of intraocular malignant tumor.

Proteomics in uveal melanoma

PURPOSE OF REVIEW

This article reviews the latest proteomic research on uveal melanoma.

RECENT FINDINGS

Proteomic analysis of uveal melanoma cell lines and tissue specimens has improved our understanding of the pathophysiology of uveal melanoma and helped identify potential prognostic biomarkers. Circulating proteins in patient serum may aid in the surveillance of metastatic disease. The proteomes of aqueous and vitreous biopsy specimens may provide safer biomarkers for metastatic risk and candidate therapeutic targets in uveal melanoma. Proteomic analysis has the potential to benefit patient outcomes by improving diagnosis, prognostication, surveillance, and treatment of uveal melanoma.

SUMMARY

These recent findings demonstrate that proteomic analysis is an important area of research to better understand the pathophysiology of uveal melanoma and improve the personalized management of our patients.

Contribution of the STAT Family of Transcription Factors to the Expression of the Serotonin 2B (HTR2B) Receptor in Human Uveal Melanoma

Uveal melanoma (UM) remains the most common intraocular malignancy among diseases affecting the adult eye. The primary tumor disseminates to the liver in half of patients and leads to a 6 to 12-month survival rate, making UM a particularly aggressive type of cancer. Genomic analyses have led to the development of gene-expression profiles that can efficiently predict metastatic progression. Among these genes, that encoding the serotonin receptor 2B (HTR2B) represents the most discriminant from this molecular signature, its aberrant expression being the hallmark of UM metastatic progression. Recent evidence suggests that expression of HTR2B might be regulated through the Janus kinase/Signal Transducer and Activator of Transcription proteins (JAK/STAT) intracellular signalization pathway. However, little is actually known about the molecular mechanisms involved in the abnormally elevated expression of the HTR2B gene in metastatic UM and whether activated STAT proteins participates to this mechanism. In this study, we determined the pattern of STAT family members expressed in both primary tumors and UM cell-lines, and evaluated their contribution to HTR2B gene expression. Examination of the HTR2B promoter sequence revealed the presence of a STAT putative target site (5′-TTC (N)3 GAA3′) located 280 bp upstream of the mRNA start site that is completely identical to the high affinity binding site recognized by these TFs. Gene profiling on microarrays provided evidence that metastatic UM cell lines with high levels of HTR2B also express high levels of STAT proteins whereas low levels of these TFs are observed in non-metastatic UM cells with low levels of HTR2B, suggesting that STAT proteins contribute to HTR2B gene expression in UM cells. All UM cell lines tested were found to express their own pattern of STAT proteins in Western blot analyses. Furthermore, T142 and T143 UM cells responded to interleukins IL-4 and IL-6 by increasing the phosphorylation status of STAT1. Most of all, expression of HTR2B also considerably increased in response to both IL-4 and IL-6 therefore providing evidence that HTR2B gene expression is modulated by STAT proteins in UM cells. The binding of STAT proteins to the −280 HTR2B/STAT site was also demonstrated by electrophoretic mobility shift assay (EMSA) analyses and site-directed mutation of that STAT site also abolished both IL-4 and IL-6 responsiveness in in vitro transfection analyses. The results of this study therefore demonstrate that members from the STAT family of TFs positively contribute to the expression of HTR2B in uveal melanoma.

RETINAL MICROVASCULAR CHANGES IN UVEAL MELANOMA FOLLOWING CONBERCEPT INJECTION AFTER PLAQUE RADIOTHERAPY AS DETECTED BY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

PURPOSE

To investigate macular microvascular characteristics imaged by optical coherence tomography angiography in patients with uveal melanoma following conbercept injections after plaque radiotherapy.

METHODS

Prospective comparative analysis comprising 15 patients with uveal melanoma with conbercept injections and 30 patients without conbercept injections after plaque radiotherapy by optical coherence tomography angiography. The conbercept group received intravitreal conbercept injections at the time of plaque removal, 1 month, 3 months, 6 months , 9 months and 12 months after plaque removal (total, 6 injections). The control group had no intravitreal conbercept injection.

RESULTS

After initiation of conbercept injections, superficial retinal vascular density in the whole image and parafoveal region were significantly higher at 6 months, whereas there was no significant difference at 9 months and 12 months. In analysis of variance analysis, superficial retinal vascular density in the whole image remained stable after conbercept injections (P = 0.069), whereas the superficial retinal vascular density decreased significantly after plaque radiotherapy in the control group (P = 0.011). In multivariable linear regression, a higher superficial retinal vascular density in the whole image region at 6 months was significantly associated with intravitreal conbercept injection (P = 0.018), wider tumor base (P = 0.026), and thinner tumor thickness (P = 0.04).

CONCLUSION

Optical coherence tomography angiography can provide a quantitative evaluation of early retinal microvascular changes after radiotherapy. Intravitreal conbercept treatment could partly relieve the retinal vascular damage in response to radiation therapy at early stage in patients with uveal melanoma; however, it may not be able to provide long-term positive functional outcomes.

Circulating tumor DNA tracking through driver mutations as a liquid biopsy-based biomarker for uveal melanoma

BACKGROUND

Uveal melanoma (UM) is the most common intraocular tumor in adults. Despite good primary tumor control, up to 50% of patients develop metastasis, which is lethal. UM often presents asymptomatically and is usually diagnosed by clinical examination and imaging, making it one of the few cancer types diagnosed without a biopsy. Hence, alternative diagnostic tools are needed. Circulating tumor DNA (ctDNA) has shown potential as a liquid biopsy target for cancer screening and monitoring. The aim of this study was to evaluate the feasibility and clinical utility of ctDNA detection in UM using specific UM gene mutations.

METHODS

We used the highly sensitive digital droplet PCR (ddPCR) assay to quantify UM driver mutations (GNAQ, GNA11, PLCβ4 and CYSTLR2) in cell-free DNA (cfDNA). cfDNA was analyzed in six well established human UM cell lines with known mutational status. cfDNA was analyzed in the blood and aqueous humor of an UM rabbit model and in the blood of patients. Rabbits were inoculated with human UM cells into the suprachoroidal space, and mutated ctDNA was quantified from longitudinal peripheral blood and aqueous humor draws. Blood clinical specimens were obtained from primary UM patients (n = 14), patients presenting with choroidal nevi (n = 16) and healthy individuals (n = 15).

RESULTS

The in vitro model validated the specificity and accuracy of ddPCR to detect mutated cfDNA from UM cell supernatant. In the rabbit model, plasma and aqueous humor levels of ctDNA correlated with tumor growth. Notably, the detection of ctDNA preceded clinical detection of the intraocular tumor. In human specimens, while we did not detect any trace of ctDNA in healthy controls, we detected ctDNA in all UM patients. We observed that UM patients had significantly higher levels of ctDNA than patients with nevi, with a strong correlation between ctDNA levels and malignancy. Noteworthy, in patients with nevi, the levels of ctDNA highly correlated with the presence of clinical risk factors.

CONCLUSIONS

We report, for the first time, compelling evidence from in vitro assays, and in vivo animal model and clinical specimens for the potential of mutated ctDNA as a biomarker of UM progression. These findings pave the way towards the implementation of a liquid biopsy to detect and monitor UM tumors.