The Anti-tumor Effect Of Acetylcholinesterase In Cacer Gene-viro Targeting Therapy System

Acetylcholinesterase (AChE) is a secretive carboxylesterase that can rapidly hydrolyze theneurotransmitter acetylcholine (Ach) at cholinergic synapses, which is vital important for the cor-rect function of the nervous system. Resent years, researchers have found that it not only existedin the nervous system, but also in other tissues and in cancers. It was reported that acetylcholinecould promote cell proliferation and inhibit cell apoptosis in some cancers, so what’s the functionof AChE in cancer cells? Is it capable that AChE can be used for gene therapy? Based on this, wehave an exploration as follows:First, the AChE levels were detected in different cancer tissues and corresponding adjacenttissues from various cancer patients, the results showed that the level of AChE was lower in can-cer tissues than the relative adjacent ones, such as in gastric, pancreatic and renal cancers.Second, the recombined plasmid armed with AChE was constructed, co-transfected293Tcells with packaging plasmid, attaining the recombined lenti-virus armed with AChE.293T anddifferent cancer cells were infected by this recombined lenti-virus, gaining the AChE stable trans-fected cell lines after sieving, the function of AChE to gastric cancer and other origin cancers weredetected seperately. The research demonstrated that AChE overexpression can’t inhibit the proli-feration of gastric cancer cell lines AGS, can not enhance the chemical drug sensitivity of AGScell, but the proliferation of liver cancer cell lines SMMC-7721was inhibited with AChE geneoverexpression. Third, replicate deficient adenovirus and replicate adenovirus armed with AChE were con-structed as Ad.AChE and ZD55.AChE seperately, their function in different cancer cell lines andfibroblast cells were detected. The results showed that Ad.AChE can inhibit gastric cancer cells’proliferation and many other kind of cancer cells’ viability were inhibited as well, but has no pro-liferate inhibition and other side effects to primary fibroblast cells. The killing effects ofZD55.AChE to gastric cancer cells more obvious than Ad.AChE and ZD55, and the same pheno-menon was observed in other kinds of tumor cells, but not in primary fibroblast cells.Fourth, the gastric cancer stem cells were sorted with flow cytometry, and the growth inhibi-tion effect of Ad.AChE and ZD55.AChE to AGS stem cells were studied. The results indicate thatboth of them have a strong inhibition for gastric cancer stem cells proliferation, especial the func-tion of ZD55.AChE.Fifth, the killing pathway was studied. Investigations illustrated that ZD55.AChE was capa-ble of accelerating caspase-dependent apoptosis in AGS cells. Besides, JC-1experimente showedthat ZD55.AChE could initiate alteration of mitochondrial membrane potential, proclaiming thatZD55.AChE induced AGS cell apoptosis was through mitochondrial pathway.Sixth, the node mouse modle with different gastric cancer cell lines MGC80-3and NCI-N87were constructed, the virus Ad.AChE and/or ZD55.AChE were injected and tumor volume weredetected in follow. The results showed that ZD55.AChE has strong anti-tumor effect on bothtransplanted tumor mouth models.Above all, this research showed that there was an obvious difference of AChE level in cancertissues and the corresponding adjacent tissues; the recombined adenovirus armed with AChE cannot only induce cell apoptosis of many kind of cancer cells and gastric cancer stem cells, but also inhibit the proliferation of in vivo transplant tumors. Therefore, AChE is a new candidate gene,and has a potential value for tumor gene-viro targeting therapy.