Growth-Arrest-Specific 7 Gene Regulates Neural Crest Formation and Craniofacial Development in Zebrafish

Loss of Gas7 Is a Key Metastatic Switch in Neuroblastoma

Metastatic spread to distant tissues and organs is responsible for most cancer-related mortalities. Changes in the invasiveness ability of metastatic tumor cells often come with significantly altered gene expression profiles compared with primary tumor cells. Identifying the main actors involved in the metastatic switch of tumor cells is key to proposed new therapeutic approaches. In this issue, the loss of growth-arrest specific 7 is described as one of the main events driving metastatic spread in neuroblastoma.See related article by Dong et al., p. 2995.

Fine-mapping and cell-specific enrichment at corneal resistance factor loci prioritize candidate causal regulatory variants

Corneal resistance factor (CRF) is altered during corneal diseases progression. Genome-wide-association studies (GWAS) indicated potential CRF and disease genetics overlap. Here, we characterise 135 CRF loci following GWAS in 76029 UK Biobank participants. Enrichment of extra-cellular matrix gene-sets, genetic correlation with corneal thickness (70% (SE = 5%)), reported keratoconus risk variants at 13 loci, all support relevance to corneal stroma biology. Fine-mapping identifies a subset of 55 highly likely causal variants, 91% of which are non-coding. Genomic features enrichments, using all associated variants, also indicate prominent regulatory causal role. We newly established open chromatin landscapes in two widely-used human cornea immortalised cell lines using ATAC-seq. Variants associated with CRF were significantly enriched in regulatory regions from the corneal stroma-derived cell line and enrichment increases to over 5 fold for variants prioritised by fine-mapping-including at GAS7, SMAD3 and COL6A1 loci. Our analysis generates many hypotheses for future functional validation of aetiological mechanisms.

Oxaliplatin inhibits proliferation and migration of human hepatocellular carcinoma cells via GAS7C and the N-WASP/FAK/F-actin pathway

The growth arrest-specific gene 7 (GAS7), a member of the growth-arrest-specific family, encodes three protein isoforms (GAS7A, GAS7B, and GAS7C) and plays a potential role in lung cancer as a tumor suppressor gene. In the present study, we found low endogenous expressions of GAS7C mRNA and protein in hepatocellular carcinoma (HCC) cell lines compared with normal liver cells, and that there was a distinct increase of GAS7C expression in HCC cells treated with oxaliplatin. CCK8, apoptosis, and Transwell migration assays showed that cell proliferation and motility of HepG2 and MHCC-97 H cells were inhibited by oxaliplatin, while apoptosis was increased. Interestingly, western blot analysis showed that treatment with oxaliplatin increased GAS7C and N-WASP protein levels and decreased the levels of proteins involved in the fibronectin/integrin/FAK pathway, such as FAK, in both HCC cell lines. In addition, ectopically overexpressed GAS7C obviously inhibited cell proliferation and cell motility. Flow cytometry results showed that overexpression of GAS7C induced apoptosis of HepG2 and MHCC-97 H cells. We further confirmed the correlation between GAS7C and the N-WASP/FAK/F-actin pathway by q-PCR and western blot analysis of in GAS7C-overexpressing HepG2 and MHCC-97 H cells. Inhibition of GAS7C substantially reversed the anti-cancer effect of oxaliplatin and blocked the activity of the N-WASP/FAK/F-actin pathway. Taken together, our results showed that oxaliplatin inhibits HCC cell proliferation and migration ability by up-regulating GAS7C and activating the N-WASP/FAK/F-actin pathway.