ABSTRACT
Metabolic abnormality is one of the hallmarks of cancer cells, and limiting material supply is a potential breakthrough approach for cancer treatment. Increasing researchers have been involved in the study of glioma cell metabolism reprogramming since the significance of IDH1 was confirmed in glioma. However, the molecular mechanisms underlying metabolic reprogramming induced by methionine deprivation regulates glioma cell proliferation remain unclear. Here we demonstrated that methionine deprivation inhibited glioma cell proliferation via downregulating interleukin 1 receptor antagonist (IL1RN) both in vitro and in vivo, methionine deprivation or knocking down IL1RN induced glioma cell cycle arrest. Moreover, we confirmed that IL1RN is a tumor associated gene and its expression is negatively correlated with the survival time of glioma patients. Altogether these results demonstrate a strong rationale insight that targeting amino acid metabolism such as methionine deprivation/IL1RN related gene therapy may offer novel direction for glioma treatment.
Subject(s)
Brain Neoplasms/metabolism , Glioma/metabolism , Interleukin 1 Receptor Antagonist Protein/biosynthesis , Methionine/deficiency , Animals , Brain Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/physiology , Down-Regulation , Glioma/pathology , Heterografts , Humans , Interleukin 1 Receptor Antagonist Protein/genetics , Mice , Mice, Inbred BALB C , Mice, Nude , RNA, Messenger/genetics , RNA, Messenger/metabolism , TransfectionABSTRACT
Objective To analyze the effect of eukaryotic expression vector containing sense and antisense DNA methyltransferase (DNMT1) gene on the transcript level of tumor associated genes in human colon cancer cell line. Methods Recombinant plasmid, including sense DNMT1 (HMT) and antisense DNMT1 (THM) gene, were constructed and transfected into SW1116 cell by using the lipofectamine. Then G418 filtration was performed. The expression of DNMT1 protein was examined by Western blotting. The transcription level of hMLH1, hMSH2, c myc and p16 INK4A genes were detected by RT PCR. Results The sense and antisense eukaryotic expression vectors were successfully constructed and then the constructed recombinant plasmids were transfected into SW1116 cell. The protein levels of DNMT1 have been up regulated and down regulated in SW1116 cells transfected with HMT and THM plasmids, respectively. The mRNA level of hMLH1, hMSH2, c myc gene were down regulated in the sense DNMT1 transfected cell. The mRNA level of hMSH2 was up regulated in the antisense DNMT1 transfected cell. However, the transcription level of p16 INK4A gene could not be associated with DNMT1 in SW1116 cell.Conclusion DNMT1 can regulate the expression of the tumor associated genes in human colon cancer cell line SW1116.
ABSTRACT
Objective To investigate the relationship of the expression of DNA methyltransferase,demethylase(mbd2) and tumor-associated genes in human gastric cancer. Methods Tissue samples of cancerous,para-cancerous and normal gastric mucosa were obtained surgically from 28 primary gastric cancer patients. The transcription level of DNA methyltransferase 1 (DNMT1),mbd2,methyl-CpG binding protein (MeCP2),p16 INK4A and c-myc were determined by using real-time RT-PCR and RT-PCR. The relationship between the expression of DNA methylation-associated genes and tumor-associated genes was analyzed. Results The mRNA level of DNMT1 was higher and the mRNA level of mbd2 gene was lower in cancerous tissue than that in normal tissue. The expression of c-myc instead of p16 INK4A and MeCP2 was increased in cancer tissues. The mRNA level of c-myc related negatively to mbd2 when gastric cancer developed. However,there was no any close relation between the transcription level of all above genes and tumor biological behavior in human gastric cancer. Conclusion This study indicates that MeCP2 but not DNMT1 may contribute to the regulation of tumor-associated genes expression in human gastric cancer.
ABSTRACT
Objective: To construct eukaryotic expression vector of tumor-associated gene SNC90 and transfect it into human colorectal cancer cell lines. Methods: A 1.5 kb tumor-associate gene SNC90 full length cDNA was inserted into a mammalian expression vector pREP9 to make recombinant vector pREP9-SNC90, which was then introduced into three kinds of colorectal cancer cell lines, SW1116, COL0205 and SW620, by lipofection or electroporation. The cells resistant to G418 drug were selected. Results: Cells transfected with pREP9-SNC90 showed fewer G418-resistant colonies than those transfected with void vector, the inhibitory rates are 72.2%, 74.2% and 59.7%, respectively. Conclusion : SNC90 may play a negative role in regulating growth of colorectal cancer cell.
