Metastasis is a complex, multistep process of cancer progression that has few treatment options. A critical event is the invasion of cancer cells into blood vessels (intravasation), through which cancer cells disseminate to distant organs. Breast cancer cells with increased abundance of Mena [an epidermal growth factor (EGF)–responsive cell migration protein] are present with macrophages at sites of intravasation, called TMEM sites (for tumor microenvironment of metastasis), in patient tumor samples. Furthermore, the density of these intravasation sites correlates with metastatic risk in patients. We found that intravasation of breast cancer cells may be prevented by blocking the signaling between cancer cells and macrophages. We obtained invasive breast ductal carcinoma cells of various subtypes by fine-needle aspiration (FNA) biopsies from patients and found that, in an in vitro transendothelial migration assay, cells that migrated through a layer of human endothelial cells were enriched for the transcript encoding MenaINV, an invasive isoform of Mena. This enhanced transendothelial migration required macrophages and occurred with all of the breast cancer subtypes. Using mouse macrophages and the human cancer cells from the FNAs, we identified paracrine and autocrine activation of colony-stimulating factor-1 receptor (CSF-1R). The paracrine or autocrine nature of the signal depended on the breast cancer cell subtype. Knocking down MenaINV or adding an antibody that blocks CSF-1R function prevented transendothelial migration. Our findings indicate that MenaINV and TMEM frequency are correlated prognostic markers and CSF-1 and MenaINV may be therapeutic targets to prevent metastasis of multiple breast cancer subtypes.
Loss-of-function mutations in the ␣3 isoform of the Na ϩ /K ϩ ATPase (sodium pump) are responsible for rapid-onset dystonia parkinsonism (DYT12). Recently, a pharmacological model of DYT12 was generated implicating both the cerebellum and basal ganglia in the disorder. Notably, partially blocking sodium pumps in the cerebellum was necessary and sufficient for induction of dystonia. Thus, a key question that remains is how partially blocking sodium pumps in the cerebellum induces dystonia. In vivo recordings from dystonic mice revealed abnormal high-frequency bursting activity in neurons of the deep cerebellar nuclei (DCN), which comprise the bulk of cerebellar output. In the same mice, Purkinje cells, which provide strong inhibitory drive to DCN cells, also fired in a similarly erratic manner. In vitro studies demonstrated that Purkinje cells are highly sensitive to sodium pump dysfunction that alters the intrinsic pacemaking of these neurons, resulting in erratic burst firing similar to that identified in vivo. This abnormal firing abates when sodium pump function is restored and dystonia caused by partial block of sodium pumps can be similarly alleviated. These findings suggest that persistent high-frequency burst firing of cerebellar neurons caused by sodium pump dysfunction underlies dystonia in this model of DYT12.
A total of 200 cell lines including different human, monkey, mice, hamster and rat cell types were examined for mycoplasma infection status. PCR assay using generic-specific universal primers showed that 40 (20%) of the cell lines are contaminated with mycoplasma. Employment of species-specific primers within these infected cell lines revealed infection with M. hyorhinis (42.5%), M. fermentas (37.5%), M. arginini (37.5%), M. orale (12.5%) and A. laidlawii (7.5%). A number of the cultures were coinfected with 2 or 3 different species. Contaminated samples were treated with BM-Cyclin, Ciprofloxacin and mycoplasma removal agent (MRA). Mycoplasma eradication was subsequently checked by PCR following 2 weeks continuous culture of treated cells in antibiotic free culture medium. Mycoplasmal infections were eradicated in 100, 70 and 42% of infected cell lines when the samples were treated with BM-Cyclin, MRA and Ciprofloxacin, respectively. However, 12% (BM-Cyclin), 62.5% (MRA) and 82.5% (Ciprofloxacin) of mycoplasma regrowth was observed 4 months after the treatment. Notably, the risk of spontaneous culture death was 17.5, 12.5 and 0% for BM-Cyclin, MRA and Ciprofloxacin, respectively.
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