New methods in the diagnosis of cancer and gene therapy of cancer based on nanoparticles

Cancer is one of the leading cause of death in the world with the prevalence of >10 million mortalities annually. Current cancer treatments include surgical intervention, radiation, and taking chemotherapeutic drugs, which often kill the healthy cells and result in toxicity in patients. Therefore, researchers are looking for ways to be able to eliminate just cancerous cells. Intra-tumor heterogeneity of cancerous cells is the main obstacle on the way of an effective cancer treatment. However, better comprehension of molecular basis of tumor and the advent of new diagnostic technologies can help to improve the treatment of various cancers. Therefore, study of epigenetic changes, gene expression of cancerous cells and employing methods that enable us to correct or minimize these changes is critically important. In this paper, we will review the recent advanced strategies being used in the field of cancer research.

Coinhibition of overexpressed genes in acute myeloid leukemia subtype M2 by gold nanoparticles functionalized with five antisense oligonucleotides and one anti-CD33(+)/CD34(+) aptamer

The aim of this study was to evaluate an engineered nanostructure to silence five important oncogenes, including BAG1, MDM2, Bcl-2, BIRC5 (survivin) and XIAP, in acute myeloid leukemia subtype 2 (AML-M2). The smart nanostructures were functionalized gold nanoparticles (FGNs) containing five antisense oligonucleotides (AOs) and one anti-CD33(+)/CD34(+) aptamer. First, the best AO for each gene was selected with the OligoWalk online software, and then different arrangements of AOs were evaluated with the RNAstructure software. Thereafter, naked gold nanoparticles (NGNs) were synthesized by the reaction of 1000 mm HAuCl4 with 10 μg ml(-1) ascorbic acid. Next, five AOs and one anti-CD33(+)/CD34(+) aptamer were attached to NGNs through serial reactions. Later, 5 ml of heparinized blood samples from five AML-M2 patients were prepared, cancerous cells were isolated and then incubated with three concentrations (75, 150 and 300 μg ml(-1)) each of FGNs, NGNs, gold nanoparticles functionalized with scrambled oligonucleotides (GNFSONs) and doxorubicin. Finally, cell death percentage and gene expressions were measured by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and real-time PCR, respectively. This study showed that FGNs and doxorubicin led to more cell death compared with NGNs and GNFSONs (P<0.05). Interestingly, all concentrations of FGNs led to a decrease in gene expression. As an important finding, although all concentrations of doxorubicin could also inhibit the expression of genes, FGNs had more effect (P<0.05). Moreover, both NGNs and GNFSONs could silence all genes only at a concentration of 300 μg ml(-1). For BCL2 and XIAP, a dose-dependent pattern was observed, but there was no similar pattern for others.