Unilateral conjunctival Classic Kaposi Sarcoma following a COVID 19 booster.

Purpose: We describe a case of Classic Kaposi's sarcoma in a functionally monocular patient following a COVID19 vaccine booster and provide compelling evidence that suggests the booster was a relevant co-factor in the initiation of the disease process. Observations: The patient presented with red, irritated conjunctival area described as "bubbling" in her right eye. While her past medical history includes hypercholesterolemia and hypertension, she had no history of a compromised immune system. Her ophthalmologic history is more complex including treatment for glaucoma. The patient has 20/20 uncorrected vision OD and LP OS. Due to her ocular co-morbidities, the patient initially received interferon alpha 2-B qid for 6 weeks. However, topical therapy failed to decrease the size of the conjunctival lesions. After referral to Radiation Oncology, the right eye/orbit was treated with electron beam therapy for 1 month which caused a marked decrease in the size and vascularity of the conjunctival lesions. A slow improvement continued during followup. Conclusion and importance: In that the vaccine booster preceded the cancer, it appears etiologic to the appearance of Kaposi's sarcoma. The patient's monocular vision and glaucoma complicated her treatment. This case expands on current concepts of cofactors needed for the development of Kaposi's sarcoma in that vaccine booster administration was relevant to tumor progression and both clinical and mechanistic evidence is presented to support this hypothesis.

Hypoxia-induced vascular endothelial growth factor secretion by retinal pigment epithelial cells is inhibited by melatonin via decreased accumulation of hypoxia-inducible factors-1α protein.

BACKGROUND: Hypoxia is the most important stimulus leading to up-regulation of vascular endothelial growth factor (VEGF) in the retina via elevation of hypoxia-inducible factors-1α (HIF-1α) protein. The purpose of this study was to test the effects of melatonin on the expression of VEGF and HIF-1α in the cultured human retinal pigment epithelial (RPE) cells under normoxia and hypoxia. METHOD: An in vitro RPE cell hypoxia model was established by placing cells under 1% oxygen pressure or by adding cobalt chloride (CoCl2 ) to the culture medium. RPE cells and conditioned media were collected from cultures treated with and without melatonin under normoxia and hypoxia. The protein and RNA levels of VEGF and HIF-1α were measured by ELISA kits and RT-PCR, respectively. RESULT: Hypoxia induced a significant increase of expression and secretion of VEGF and accumulation of HIF-1α protein in RPE cells (P < 0.05). Melatonin at 10-5 to 10-8 M significantly inhibited hypoxia-induced expression, the secretion of VEGF and the accumulation of HIF-1α protein (P < 0.05), but not affected expression of VEGF and HIF-1α under normoxia (P > 0.05). CONCLUSION: This study suggests that melatonin may have potential value in the prevention and treatment of various retinal diseases associated with increase of VEGF, vascular leakage and angiogenesis.

Nonlethal Levels of Zeaxanthin Inhibit Cell Migration, Invasion, and Secretion of MMP-2 via NF-κB Pathway in Cultured Human Uveal Melanoma Cells.

Zeaxanthin at nonlethal dosages (3-10 µM) significantly inhibited the cell migration of cultured uveal melanoma cells (C918 cell line) as determined by wound healing assay and Boyden chamber assay. Matrigel invasion assay showed that cell invasion of uveal melanoma cells could be significantly inhibited by zeaxanthin. Secretion of MMP-2 by melanoma cells was significantly inhibited by zeaxanthin in a dose-dependent manner as measured by ELISA kit. Zeaxanthin also significantly inhibited the NF-κB levels in nuclear extracts of the UM cells, which is the upstream of the MMP-2 secretion. These results suggest that zeaxanthin might be a potentially therapeutic approach in the prevention of metastasis in uveal melanoma.

A Hyalinized Trichilemmoma of the Eyelid in a Teenager.

A 16-year-old African American male, the youngest patient to date, presented with a well-circumscribed upper eyelid lesion. On excision, the dermal nodule was contiguous with the epidermis, displayed trichohyalin-like bodies in an expanded outer root sheath, and was composed chiefly of small cellular clusters separated by a prominent network of periodic acid Schiff -positive hyaline bands of basement membrane material. The tumor cells were positive for high molecular weight cytokeratins (CK) 5/6, CK14, and CK34ßE12 and were negative for CK7, carcinoembryonic antigen and epithelial membrane antigen. Negative S100, glial fibrillary acidic protein, and smooth muscle actin immunoreactions ruled out a myoepithelial lesion. The Ki-67 proliferation index was <10%. The diagnosis was a hyalinized trichilemmoma, contrasting with the more common lobular type. As an isolated lesion, trichilemmoma does not portend Cowden syndrome.