[Effects of Toosendanin on the formation of CTPS cytoophidium in human gastric cancer cell MKN-45 and its mechanism].

To investigate the relationship between toosendanin(TSN) and CTP synthase(CTPS) cytoophidium formation in gastric cancer MKN-45 cells. In this study, the experimental material is MKN-45 human gastric cancer cells. It contains 7 treatment groups of 0, 20, 40, 60, 80, 100, and 120 nmol/L TSN. Each group was treated in triplex privately for 24、48 and 72 hours. Cell counting kit-8 (CCK8) was used to detect the inhibitory effect of TSN on the proliferation of MKN-45 cells. After immunofluorescence detection, the morphology of CTPS cells was observed by a laser confocal microscope. The effect of TSN on MYC gene expression was detected by qRT-PCR. In addition, it contains 2 treatment groups of 1 mmol/L DON and 1 mmol/L MPA, each group was treated in triplex privately for 6 hours and then the cytoophidium morphology was detected by immunofluorescence. The results of immunofluorescence showed that CTPS formed a filamentous cytoophidium structure after treating MKN-45 cells with 1 mmol/L DON and 1 mmol/L MPA, which means that the cells have the ability to form CTPS cytoophidium; The cell proliferation rate of TSN treatment group was significantly lower than that of 0 nmol / L TSN group (＜0.01); Immunofluorescence results showed that CTPS cytoophidium was the most abundant in MKN-45 cells after treated with 80 nmol/L TSN for 72 h. The results of qRT-PCR showed that MYC expression in cells was significantly decreased after treated with 80 nmol/L TSN for 24 h (＜0.05), and MYC expression was significantly increased after 48 h (＜0.01), and then decreased. Toosendanin may affect intracellular cytoophidium assembling by regulating the expression of MYC.