Mound-like Epiretinal Material: Its Short-term Changes and Association with Posterior Vitreous Detachment.

PURPOSE: To describe clinical characteristics of a retinal finding termed mound-like epiretinal material (MOLEM), and distinguish it from epiretinal proliferation, a similar epiretinal finding previously described in various pathologies. METHODS: Five eyes from five patients were retrospectively identified from medical records. Clinical findings and images, including fundus photographs and optical coherence tomography (OCT), were reviewed. RESULTS: All eyes displayed mound-like material with uniform and low-to-moderate reflectivity on an otherwise intact retinal surface detected on OCT. No eyes presented with concurrent pathology typically observed in cases of epiretinal proliferation, such as lamellar/full-thickness macular hole, epiretinal membrane, vitreomacular traction, or uveitis. Two eyes exhibited central serous chorioretinopathy, but there was no association of MOLEM with serous retinal detachment. In three out of five eyes, MOLEM appeared simultaneously with posterior vitreous detachment (PVD). Some lesions underwent irregular transformations over months and occasionally disappeared. While all cases were monitored without intervention, no visual decline or complications attributed to MOLEM were detected. CONCLUSION: MOLEM represents a novel clinical finding, characterized by transient morphological changes without symptoms and potential association with PVD. It may occur in eyes lacking macular diseases linked with epiretinal proliferation, a similar yet distinct lesion. The incidence, etiology, and clinical significance of MOLEM warrant further investigation by accumulating comparable cases, although the lesion appears benign and self-limiting.

Elevated Na+/H+ exchanger-1 expression enhances the metastatic collective migration of head and neck squamous cell carcinoma cells.

Cancer cells can migrate as collectives during invasion and/or metastasis; however, the precise molecular mechanisms of this form of migration are less clear compared with single cell migration following epithelial-mesenchymal transition. Elevated Na+/H+ exchanger1 (NHE1) expression has been suggested to have malignant roles in a number of cancer cell lines and in vivo tumor models. Furthermore, a metastatic human head and neck squamous cell carcinoma (HNSCC) cell line (SASL1m) that was isolated based on its increased metastatic potential also exhibited higher NHE1 expression than its parental line SAS. Time-lapse video recordings indicated that both cell lines migrate as collectives, although with different features, e.g., SASL1m was much more active and changed the direction of migration more frequently than SAS cells, whereas locomotive activities were comparable. SASL1m cells also exhibited higher invasive activity than SAS in Matrigel invasion assays. shRNA-mediated NHE1 knockdown in SASL1m led to reduced locomotive and invasive activities, suggesting a critical role for NHE1 in the collective migration of SASL1m cells. SASL1m cells also exhibited a higher metastatic rate than SAS cells in a mouse lymph node metastasis model, while NHE1 knockdown suppressed in vivo SASL1m metastasis. Finally, elevated NHE1 expression was observed in human HNSCC tissue, and Cariporide, a specific NHE1 inhibitor, reduced the invasive activity of SASL1m cells, implying NHE1 could be a target for anti-invasion/metastasis therapy.