LncRNA FOXC2-AS1 stimulates proliferation of melanoma via silencing p15 by recruiting EZH2
EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES
Authors: Xu, D-F; Tao, X-H; Yu, Y.; Teng, Y.; Huang, Y-M; Ma, J-W; Fan, Y-B
Abstract
OBJECTIVE: The aim of this study was to elucidate the role of FOXC2-AS1 in promoting the proliferative ability and inhibiting apoptosis of melanoma by silencing p15, thereafter regulating the progression of melanoma. PATIENTS AND METHODS: FOXC2-AS1 levels in melanoma patients with or without metastasis and those with the tumor in different stages were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Regulatory effects of FOXC2-AS1 on viability and apoptosis in melanoma cells were assessed, and subcellular distribution of FOXC2-AS1 was analyzed. Subsequently, the interactions of FOXC2-AS1 with EZH2 and SUZ12 were explored by RNA-Binding Protein Immunoprecipitation (RNA-RIP) assay. Through chromatin immunoprecipitation (ChIP) assay, the role of FOXC2-AS1 to regulate p15 transcription by recruiting EZH2 was verified. At last, regulatory effects of FOXC2-AS1/p15 axis on viability and apoptosis in melanoma cells were investigated. RESULTS: It was found that FOXC2-AS1 was upregulated in melanoma tissues, especially those with metastasis or stage II-IV. Melanoma patients expressing high level of FOXC2-AS1 showed worse survival than those with low level. Knockdown of FOXC2-AS1 inhibited viability, and stimulated apoptosis in A375 and sk-me1-110 cells. Besides, P15 level was upregulated in melanoma cells transfected with si-FOXC2-AS1, and FOXC2-AS1 was mainly distributed in cytoplasm. RNA-RIP assay confirmed that FOXC2AS1 was mainly enriched in anti-EZH2 and aniti-SUZ12. Knockdown of EZH2 could markedly upregulate protein level of p15 in melanoma cells. Furthermore, it was verified that FOXC2-AS1 inhibited p15 transcription via recruiting EZH2, and the knockdown of p15 could partially reverse the regulatory effects of FOXC2-AS1 on viability and apoptosis in melanoma. CONCLUSIONS: FOXC2-AS1 stimulates proliferative ability in melanoma via silencing p15.
Low-grade Schwann cell neoplasms with leptomeningeal dissemination: clinicopathologic and autopsy findings
HUMAN PATHOLOGY
Authors: Rodriguez, Erika F.; Blakeley, Jaishri; Langmead, Shannon; Olivi, Alessandro; Tufaro, Anthony; Tabbarah, Abeer; Berkenblit, Gail; Sacks, Justin M.; Newsome, Scott D.; Montgomery, Elizabeth; Rodriguez, Fausto J.
Abstract
Leptomeningeal dissemination of low-grade Schwann cell neoplasms is an exceptionally rare occurrence and has not been well documented in the literature. We encountered 2 cases of leptomeningeal dissemination of low-grade Schwann cell neoplasms. Patient 1 was a 63-year-old woman with neurofibromatosis type 1 and a progressive low-grade malignant peripheral nerve sheath tumor developing from a diffuse/plexiform orbital neurofibroma that arose in childhood. The neoplasm demonstrated local and leptomeningeal dissemination intracranially leading to the patient's death. There was partial loss of H3K27 tri-methylation, p16 and collagen IV. Patient 2 was a 60-year-old man without neurofibromatosis type 1 who presented with cranial nerve symptoms and a disseminated neoplasm with a Schwann cell phenotype. The neoplasm stabilized after irradiation and chemotherapy, but the patient died of medical complications. Autopsy findings documented disseminated leptomeningeal disease in the intracranial and spinal compaituient. H3K27M tri-methylation was preserved. The clinicopathologic and autopsy findings are studied and presented, and the literature is reviewed. (C) 2016 Elsevier Inc. All rights reserved.