ABSTRACT
Aim To investigate the effect of m6A demethylase FTO inhibitor(FB23-2)on human glioblastoma stem cell activity. Methods The effects of FB23-2 and Temozolomide on GSC were detected by CCK-8 assay and neurosphere formation assay. The effect of FB23-2 on self-renewal of GSC was detected by limited dilution assay in vitro. The effect of FB23-2 on the proliferation of GSC was detected by EdU method. The effect of FB23-2 on apoptosis of glioblastoma stem cells was detected by flow cytometry. Results CCK-8 assay showed that FB23-2 could effectively inhibit the cell viability of GSC with IC50 values of 7.11 μmol·L-1 and 4.63 μmol·L-1,respectively. The size and number of GSC neural sphere in FB23-2 treatment group were significantly reduced compared with control group. In vitro limited dilution experiment showed that FB23-2 effectively inhibited the self-renewal ability of GSC. EdU incorporation experiment showed that compared with the control group,the treatment group decreased to(70.59±13.74)% and(50.33±4.53)%,respectively. The apoptotic rates of the treated group were(12.16±1.90)% and(16.77±1.17)% by flow cytometry. Conclusions FTO inhibitor FB23-2 can effectively inhibit GSC growth,self-renewal and the formation of neural sphere. In addition,FB23-2 can inhibit the proliferation of GSC and induce its apoptosis.
ABSTRACT
Hirschsprung's disease (HSCR) is a common developmental anomaly of the gastrointestinal tract in children. The most significant characteristics of aganglionic segments in HSCR are hyperplastic extrinsic nerve fibers and the absence of endogenous ganglion plexus. Double C2 domain alpha (DOC2A) is mainly located in the nucleus and is involved in Ca2+-dependent neurotransmitter release. The loss function of DOC2A influences postsynaptic protein synthesis, dendrite morphology, postsynaptic receptor density and synaptic plasticity. It is still unknown why hyperplastic extrinsic nerve fibers grow into aganglionic segments in HSCR. We detected the expression of DOC2A in HSCR aganglionic segment colons and established three DOC2A-knockdown models in the Neuro-2a cell line, neural spheres and zebrafish separately. First, we detected the protein and mRNA expression of DOC2A and found that DOC2A was negatively correlated with AChE+ grades. Second, in the Neuro-2a cell lines, we found that the amount of neurite outgrowth and mean area per cell were significantly increased, which suggested that the inhibition of DOC2A promotes nerve fiber formation and the neuron's polarity. In the neural spheres, we found that the DOC2A knockdown was manifested by a more obvious connection of nerve fibers in neural spheres. Then, we knocked down Doc2a in zebrafish and found that the down-regulation of Doc2a accelerates the formation of hyperplastic nerve fibers in aganglionic segments in zebrafish. Finally, we detected the expression of MUNC13-2 (UNC13B), which was obviously up-regulated in Grade3/4 (lower DOC2A expression) compared with Grade1/2 (higher DOC2A expression) in the circular muscle layer and longitudinal muscle layer. The expression of UNC13B was up-regulated with the knocking down of DOC2A, and there were protein interactions between DOC2A and UNC13B. The down-regulation of DOC2A may be an important factor leading to hyperplastic nerve fibers in aganglionic segments of HSCR. UNC13B seems to be a downstream molecule to DOC2A, which may participate in the spasm of aganglionic segments of HSCR patient colons.
