ABSTRACT
In order to better understand the role of HIF-1α in the proliferation of the retinoblastoma cells, a siRNA knockdown of HIF-1α followed by a proliferation assay was performed. Further sequencing was then carried out in order to assess knockdown efficiency and expression of HIF-1α. Upregulation of HIF-1α gene expression in CoCl2-treated retinoblastoma cells was demonstrated via melting curve analysis from PCR tests and was further analyzed using western blot and densitometry analysis. Reduction of HIF-1α expression in retinoblastoma, post HIF-1α knockdown, was observed after siRNA transfection into Y-79 cells. Knockdown of HIF-1α resulted in a significant decrease in proliferation thereby demonstrating that HIF-1α is involved in promoting survival and proliferation in retinoblastoma cells. Stabilization of HIF-1α in retinoblastoma cells using CoCl2 was unsuccessful.
Subject(s)
Cell Proliferation , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Retinal Neoplasms/metabolism , Retinal Neoplasms/pathology , Retinoblastoma/metabolism , Retinoblastoma/pathology , Apoptosis , Blotting, Western , Cell Hypoxia , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/antagonists & inhibitors , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , RNA, Messenger/genetics , RNA, Small Interfering/genetics , Real-Time Polymerase Chain Reaction , Retinal Neoplasms/genetics , Retinoblastoma/genetics , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured , Up-RegulationABSTRACT
Paracoccidioidomycosis (PCM) is the most prevalent systemic mycosis in immunocompetent individuals in Brazil. Ocular infection by PCM is rare; however, when infection does occur, the most common ocular sites involved are eyelid and conjunctiva. A 68-year-old white male presented with a 2-month history of a painless, ulcerated, infiltrative and diffuse whitish lesion located on the right inferior eyelid. A clinical diagnosis of malignant tumor, possibly squamous cell carcinoma, was made. The histopathologic examination showed a hyperplastic epithelium with inflammatory infiltrate of lymphocytes, plasma cells, neutrophils and histiocytes. Large numbers of giant cells were also present. Periodic acid Schiff and Grocott (silver methenamine) stains showed several large round structures with peripheral lateral small budding cells that resembled a "ship's wheel". No multinucleated fungi were seen. The fungi varied in size and small forms were round and single fungal structures. A diagnosis of paracoccidioidomycosis was made PCM eyelid infection is rare and can simulate carcinoma both clinically and histopathologically.
