Cytotoxic Effect Of Methylmercury-L-Cys Conjugate Targeted On Glioma Celts Through LAT1

In our long-term research in MMC molecules mechanism based on thedeveloping brain damage, and through experiment prove its obvious antitumoractivity in vivo and in vitro, and "MMC used for the preparation of intracranialmalignant tumor cancer drugs new USES for" the national invention patent license.As anti-cancer drugs, in addition to consider its curative effect, its adverse reactionsare also factors must be considered. Based on macromolecule neutral amino acidtransport carrier (LAT1) were not expressed in normal astrocytes, glioma cellsincreased, its expression level increased with the increase of tumor malignant degree;Other malignant glioma cells of methionine high intake, the intake is associated withmalignant degree of gliomas are. MeHg-L-cys conjugate is LAT1transshipmentsubstrate methionine competitive analogue, accordingly we MeHg-L-cys conjugateeffects by LAT1targeting glioma cell toxicity research.Objective: from the perspective of transshipment molecular biology, the use ofLAT1in glioma cells and biological differences between normal tissue cells,investigate MeHg-L-cys conjugate content via the LAT1enhance its brain gliomastargeted transshipment and cytotoxic effects. This study aims to promote MeHg-L-cys conjugate content targeted transfer to glioma cells, enhances its targeted attackability of glioma cells, relieve adverse effects on normal brain tissue, the curativeeffect of further optimization of MMC in the treatment of glioma.Methods:1. In vitro research: In vitro C6glioma cells with different concentration of MMCand MeHg-L-cys treatmented, with a determined by MTT method to detect the influence on glioma cells survive; C6glioma cells with different concentration ofMMC and MeHg-L-cys treatmented, used AnnexinV-FITC and PI double dyedetection of MMC and MeHg-L-cys on C6glioma cell apoptosis and cell cycle.2. In vivo research: preparation of C6rat glioma models,1week afterinoculationed C6cells, brain MRI tested, determined the modeling was successful.About5mm selected from18tumors in rats, were randomly divided into control group,the MMC group, MeHg-L-cys conjugate group,2group, gastric gavage10mg/(kgBW d) MMC and MeHg-L-cys, continuous3d, after waiting for groups ofanimals died a natural death or plan execution, the anatomy of the brain tissue,respectively, with gross and histologic examination, determination of tumors volume,detection of tumors, and brain tissue mercury levels, and each group a tumor-burdenedsurvival time of rats.Results:1. In vitro experiment: MMC and MeHg-L-cys for C6rat glioma cells survivehad obvious inhibition, was dose dependent; Both could induced C6rat glioma cellapoptosis; Reduced stagnation of glioma cells in G0/G1to S phase cell ratio.2. In vivo study: Tumor-burdened bone in rats after1week or so began to appearall sorts of nervous system symptoms, MRI imaging observation tumors had increasedwith the increase of tumor age increased. Pathology examination showed: dense tumorcells arranged disorder, nuclear fission as easy to see, in the tumor vascular tissue,tumor invasive growth was finger into the surrounding normal tissue. Tumor cells, glialacidic fiber protein expression was positive. Tumor volume result showed: theexperimental group were given12rats after drug treatment, tumor volume wassignificantly reduced, MeHg-L-cys group decreased more significantly than MMCgroups of tumor size. Mercury content determination results showed that MMC groupof tumors had mercury levels was8.017+/-0.265mu g/g, brain tissue mercurycontent is7.153+0.495u g/g; MeHg-L-brain mercury cys group was8.390+/-0.401mu g/g, brain tissue mercury content is7.040+0.641u g/g; Mercury controltumors and brain tissue wasn’t content at all. Two experimental tumors, and brain tissue mercury levels were higher than control group (P <0.05); MeHg-L-cystumors had mercury levels higher than that of MMC group (P <0.05); MeHg-L-cysbrain tissue in mercury lower than that of MMC group (P <0.05).Survival resultsshowed: the control group a tumor-burdened rats median survival time was18d,average survival time was (18+7) d; MMC tumor-burdened group rats the mediansurvival time was23d, average survival time was (23+11) d; MeHg-L-cystumor-burdened group rats the median survival time was32d, average survival timewas (32+14) d. MMC and MeHg-L-cys group a tumor-burdened animal survivaltime was longer than the control group; MeHg-L-cys group a tumor-burdenedanimal survival time was longer than MMC group. In addition to natural death, MeHg-L-cys group remaining two rats in the50thd were executed.Conclusions:1. MMC and MeHg-L-cys conjugate appears dose dependent inhibition of C6rat glioma cells survive.2. MMC and MeHg-L-cys conjugate can induction of glioma cell apoptosis andinhibit cell cycle process, increase the percentage of G0/G1phase, the ratio of S phasecells.3. The C6rat glioma model animals are given MMC and MeHg-L-cysconjugate drugs, can inhibit the growth of glioma.4. The C6rat glioma model animals give MeHg-L-cys conjugate content aftertreatment, tumors mercury levels higher than that of MMC group (P<0.05).5. The C6rat glioma model animals give MMC and MeHg-L-cys conjugatedrugs, extended a tumor-burdened animal survival compared with control group,MeHg-L-cys conjugate longer survival time than MMC group.