RESUMO
Aim: To investigate potential DNA methylation in methylcytosine dioxygenases and correlation of TET genes with vitamin B12/ferritin levels in cancer patients. Materials & methods: 200 blood samples were obtained from both cancer patients and healthy individuals. Results: The expression of DNMT1, DNMT3a and DNMT3b was increased in patients with low vitamin B12 and ferritin levels, while the expression of MTR, TET1 and TET3 significantly decreased. DNA methylation analysis in patients with deficient vitamin B12/ferritin levels showed methylomic changes within the location 318/CG and 385/CG in the promoter region of TET1 and TET3, respectively. Conclusion: Vitamin B12/ferritin deficiency contributes to DNA methylation progress in cancer patients.
Assuntos
Dioxigenases , Neoplasias , 5-Metilcitosina/metabolismo , Metilação de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/genética , Dioxigenases/metabolismo , Epigênese Genética , Ferritinas/metabolismo , Humanos , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Neoplasias/complicações , Neoplasias/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/genética , Vitamina B 12RESUMO
OBJECTIVES: This study was conducted to investigate the potential anticancer properties of N, N-dibenzyl asparagine (NNDAsp), as an Asparagine (Asp) analog, using colon cancer Caco-2 cell and the normal NCM-460 cell line. METHODS: Cell viability rate and levels of produced lactate dehydrogenase (LDH) were achieved upon treatment with NNDAsp compared to Asp treatment using MTT assay and LDH production kit. The protein expression profile of asparagine synthetase (ASNS) was achieved by using ELISA and flow cytometry assay. The levels of released inflammatory cytokines, including interleukin-1 alpha (IL-1α) and IL-1 beta (IL-ß), were monitored using an ELISA assay. RESULTS: Our findings showed significant inhibition of colon cancer cell proliferation accompanied by a high level of produced LDH in a dose-dependent of an NNDAsp treatment without detectable toxic effect in normal cells. Interestingly, NNDAsp showed competitive inhibition of ASNS protein expression, in almost 3% of stained cancer cells, compared to 18% and 35% of untreated cells and cells pre-treated with Asp, respectively. Likewise, the concentration of ASNS protein was dramatically depleted in a dose and time-dependent of NNDAsp treatment in comparison with Asp treatment indicated by ELISA assay. Furthermore, as an apoptotic indicator, the expression of P53 and Caspase 3 (Caps3) was significantly increased in Caco-2 cells treated with NNDAsp at both RNA and protein levels. In contrast, their expression was markedly depleted in Asp-treated cells. In addition, the expression of both IL-1α and IL-1 ß was markedly increased in Caco-2 cells in a dose and time-dependent of NNDAsp exogenous treatment. Moreover, targeting of ASNS by the Asp analog, NNDAsp, was further confirmed by the docking analysis of inhibitors ligands and crystal structure of ASNS protein. CONCLUSION: These data provide evidence for the effectiveness of NNDAsp in cancer treatment via selective degradation of ASNS protein expression in colon cancer cells.