The BE (2)-M17 cell line has a better dopaminergic phenotype than the traditionally used for Parkinson´s research SH-SY5Y, which is mostly serotonergic.

SH-SY5Y is a cell line derived from human neuroblastoma. It is one of the most widely used in vitro models to study Parkinson's disease. Surprisingly, it has been found that it does not develop a dopaminergic phenotype after differentiation, questioning its usefulness as a Parkinson's model. There are other in vitro models with better dopaminergic characteristics. BE (2)-M17 is a human neuroblastoma cell line that differentiates when treated with retinoic acid. We compared the dopaminergic and serotonergic properties of both cell lines. BE (2)-M17 has higher basal levels of dopaminergic markers and acquires a serotonergic phenotype during differentiation while maintaining the dopaminergic phenotype. SH-SY5Y has higher basal levels of serotonergic markers but does not acquire a dopaminergic phenotype upon differentiation.

CD43 (sialophorin) is involved in the induction of extracellular matrix remodeling and angiogenesis by lung cancer cells.

Aberrant expression of CD43 in malignant tumors of nonhematopoietic origin such as those from lung, cervix, colon, and breast has been shown to correlate with poor prognosis, providing tumor cells with enhanced motility, anchorage-independent growth, and in vivo tumor size, while protecting the cells of NK lysis and apoptosis. To further characterize the role of CD43 in cell transformation, we tested whether interfering its expression modified the capacity of the A549 non-small cell lung cancer cells to secrete molecules contributing to malignancy. The proteomic analysis of the secretome of serum-starved A549 cells revealed that cells expressing normal levels of CD43 released significantly high levels of molecules involved in extracellular matrix organization, angiogenesis, platelet degranulation, collagen degradation, and inflammation, as compared to CD43 RNAi cells. This data reveals a novel and unexpected role for CD43 in lung cancer development, mainly in remodeling the tumor microenvironment.

Disruption of TFIIH activities generates a stress gene expression response and reveals possible new targets against cancer.

Disruption of the enzymatic activities of the transcription factor TFIIH by the small molecules Triptolide (TPL) or THZ1 could be used against cancer. Here, we used the MCF10A-ErSrc oncogenesis model to compare the effect of TFIIH inhibitors between transformed cells and their progenitors. We report that tumour cells exhibited highly increased sensitivity to TPL or THZ1 and that the combination of both had a synergic effect. TPL affects the interaction between XPB and p52, causing a reduction in the levels of XPB, p52 and p8, but not other TFIIH subunits. RNA-Seq and RNAPII-ChIP-Seq experiments showed that although the levels of many transcripts were reduced, the levels of a significant number were increased after TPL treatment, with maintained or increased RNAPII promoter occupancy. A significant number of these genes encode for factors that have been related to tumour growth and metastasis, suggesting that transformed cells might rapidly develop resistance to TPL/THZ inhibitors. Some of these genes were also overexpressed in response to THZ1, of which depletion enhances the toxicity of TPL, and are possible new targets against cancer.

Kv1.3 channel blockade with the Vm24 scorpion toxin attenuates the CD4+ effector memory T cell response to TCR stimulation.

BACKGROUND: In T cells, the Kv1.3 and the KCa3.1 potassium channels regulate the membrane potential and calcium homeostasis. Notably, during TEM cell activation, the number of Kv1.3 channels on the cell membrane dramatically increases. Kv1.3 blockade results in inhibition of Ca2+ signaling in TEM cells, thus eliciting an immunomodulatory effect. Among the naturally occurring peptides, the Vm24 toxin from the Mexican scorpion Vaejovis mexicanus is the most potent and selective Kv1.3 channel blocker known, which makes it a promissory candidate for its use in the clinic. We have shown that addition of Vm24 to TCR-activated human T cells inhibits CD25 expression, cell proliferation and reduces delayed-type hypersensitivity reactions in a chronic inflammation model. Here, we used the Vm24 toxin as a tool to investigate the molecular events that follow Kv1.3 blockade specifically on human CD4+ TEM cells as they are actively involved in inflammation and are key mediators of autoimmune diseases. METHODS: We combined cell viability, activation, and multiplex cytokine assays with a proteomic analysis to identify the biological processes affected by Kv1.3 blockade on healthy donors CD4+ TEM cells, following TCR activation in the presence or absence of the Vm24 toxin. RESULTS: The peptide completely blocked Kv1.3 channels currents without impairing TEM cell viability, and in response to TCR stimulation, it inhibited the expression of the activation markers CD25 and CD40L (but not that of CD69), as well as the secretion of the pro-inflammatory cytokines IFN-γ and TNF and the anti-inflammatory cytokines IL-4, IL-5, IL-9, IL-10, and IL-13. These results, in combination with data from the proteomic analysis, indicate that the biological processes most affected by the blockade of Kv1.3 channels in a T cell activation context were cytokine-cytokine receptor interaction, mRNA processing via spliceosome, response to unfolded proteins and intracellular vesicle transport, targeting the cell protein synthesis machinery. CONCLUSIONS: The Vm24 toxin, a highly specific inhibitor of Kv1.3 channels allowed us to define downstream functions of the Kv1.3 channels in human CD4+ TEM lymphocytes. Blocking Kv1.3 channels profoundly affects the mRNA synthesis machinery, the unfolded protein response and the intracellular vesicle transport, impairing the synthesis and secretion of cytokines in response to TCR engagement, underscoring the role of Kv1.3 channels in regulating TEM lymphocyte function.