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Photodynamic therapy (PDT) induces selective cell death of neoplastic tissue and connecting vasculature by combining photosensitizers with light. Here we clarified the types of cell death induced by PDT in combination with the photosensitizer talaporfin sodium (mono-L-aspartyl chlorine e6, NPe6) in order to evaluate the potential of this therapy as a treatment for glioma. PDT with NPe6 (NPe6-PDT) induces dose-dependent cell death in human glioblastoma T98G cells. Specifically, cell death modalities were observed in NPe6-PDT treated T98G cells, including signs of apoptosis (activation of caspase-3, expression of phosphatidylserine, and DNA fragmentation) and necrosis (stainability of propidium iodide). In addition, high doses of NPe6-PDT decreased the proportion of apoptotic cell death, while increasing necrosis. Closer examination of apoptotic characteristics revealed release of cytochrome-c from mitochondria as well as activation of both caspse-9 and caspase-3 in cells treated with low doses of NPe6-PDT. Benziloxycarbonyl-Leu-Gln(OMe)-His-Asp(OMe)-fluoromethyl-ketone (Z-LEHD-fmk), a caspase-9 specific inhibitor, and benziloxycarbonyl-Asp(OMe)-Gln-Met-Asp(OMe)-fluoromethyl-ketone (Z-DQMD-fmk), a caspase-3 specific inhibitor, showed dose-dependent prevention of cell death in NPe6-PDT treated cells, indicating that mitochondrial apoptotic pathway was a factor in the observed cell death. Further, the cell morphology was observed after PDT. Time- and NPe6-dose dependent necrotic features were increased in NPe6-PDT treated cells. These results suggest that NPe6-PDT could be an effective treatment for glioma if used in mild doses to avoid the increased necrosis that may induce undesirable obstacles.

By exome sequencing, we found de novo SMARCB1 mutations in two of five individuals with typical Coffin-Siris syndrome (CSS), a rare autosomal dominant anomaly syndrome. As SMARCB1 encodes a subunit of the SWItch/Sucrose NonFermenting (SWI/SNF) complex, we screened 15 other genes encoding subunits of this complex in 23 individuals with CSS. Twenty affected individuals (87%) each had a germline mutation in one of six SWI/SNF subunit genes, including SMARCB1, SMARCA4, SMARCA2, SMARCE1, ARID1A and ARID1B.

Mutations in the components of the SWItch/sucrose nonfermentable (SWI/SNF)-like chromatin remodeling complex have recently been reported to cause Coffin-Siris syndrome (CSS), Nicolaides-Baraitser syndrome (NCBRS), and ARID1B-related intellectual disability (ID) syndrome. We detail here the genotype-phenotype correlations for 85 previously published and one additional patient with mutations in the SWI/SNF complex: four with SMARCB1 mutations, seven with SMARCA4 mutations, 37 with SMARCA2 mutations, one with an SMARCE1 mutation, three with ARID1A mutations, and 33 with ARID1B mutations. The mutations were associated with syndromic ID and speech impairment (severe/profound in SMARCB1, SMARCE1, and ARID1A mutations; variable in SMARCA4, SMARCA2, and ARID1B mutations), which was frequently accompanied by agenesis or hypoplasia of the corpus callosum. SMARCB1 mutations caused "classical" CSS with typical facial "coarseness" and significant digital/nail hypoplasia. SMARCA4 mutations caused CSS without typical facial coarseness and with significant digital/nail hypoplasia. SMARCA2 mutations caused NCBRS, typically with short stature, sparse hair, a thin vermillion of the upper lip, an everted lower lip and prominent finger joints. A SMARCE1 mutation caused CSS without typical facial coarseness and with significant digital/nail hypoplasia. ARID1A mutations caused the most severe CSS with severe physical complications. ARID1B mutations caused CSS without typical facial coarseness and with mild digital/nail hypoplasia, or caused syndromic ID. Because of the common underlying mechanism and overlapping clinical features, we propose that these conditions be referred to collectively as "SWI/SNF-related ID syndromes".