Apoptosis was considered to get the main cause of cell death induced by chemosensitizer. Latest studies indicated that stimulation of TLR9 with CpG ODN enhanced apoptosis in murine or human tumor cells but ODN M362 promotes cell proliferation and survival in hu guy hepatocellular carcinomas So we pare the direct cytotoxicity of CpG ODN and ODN M362 toward HepG2 cells, our final results showed that CpG ODN induced PF-562271 ic50 considerable inhibition in the survival of HepG2 cells, and ODN M362 had not direct cytotoxicity toward HepG2 cells we next documented that apoptosis was respon sible for CpG ODN and or 5 FU induced cytotoxicity of HepG2 cells employing MTS assay, observation of cell morph ology, Hoechst 33258 staining, and annexin V FITC staining these effects indicated that CpG ODN elevated the chemosensitivity of 5 FU in HepG2 cells by raising apoptosis without having the need to have for immune method of host.
While several scientific studies have been fo cused about the immunotherapeutic applications of CpG ODN by modulating immune program of tumor bearing hosts some latest information showed that direct cytotox icity against tumor cells is promising for Saracatinib treatment of various malignancies These earlier research strongly sup ported our study, these outcomes showed that CpG ODN immediately induced apoptosis and greater the chemosensi tivity of 5 FU in HepG2 human hepatoma cells. Cell cycle arrest was imagined to be a different major rea son of cell death induced by anti tumor medication Fluorouracil is often a pyrimidine analogue which can be transformed inside the cell into distinct cytotoxic me tabolites after which incorporates into DNA and RNA, fi nally inducing cell cycle arrest and apoptosis by inhibiting the cells capability to synthesize DNA. It is an S phase unique drug and only lively during sure cell cycles. In this examine, seven.
five ug ml of five FU induced cell cycle arrest at S phase, which was in line with prior examine Meanwhile, we discovered that two uM or 4 uM of CpG ODN in bination with seven. five ug ml of 5 FU could fur ther induce cells cycle arrest at S phase when pared with 5 FU alone These findings suggest that CpG ODN in bination with five FU induced apoptosis by interrupting the transition of cell cycle from S phase into G2 M phase, suggesting the chemosensitizing result of CpG ODN was linked to cell cycle arrest at S phase. The upregulation of Bcl two expression triggered resistance to chemotherapeutic medication and radiotherapy, even though the downregulation of Bcl 2 expression may well market apop totic response to anticancer medication Authentic time quantitative PCR experiments showed that CpG ODN and five FU alone inhibited the expression of Bcl two within HepG2 cells. Additionally, CpG ODN treatment sup pressed the expression of Bcl two in the dose dependent method These results advised the apoptosis induced by CpG ODN and five FU is related to the downregulation of Bcl two, however the precise molecular mechanism requirements even more study.