Gold@Silica Nanoparticles Functionalized with Oligonucleotides: A Prominent Tool for the Detection of the Methylated Reprimo Gene in Gastric Cancer by Dynamic Light Scattering

• Main Authors: María José Marchant, Leda Guzmán, Alejandro H. Corvalán, Marcelo J. Kogan
• Format: Article
• Language: English
• Published: MDPI AG 2019-09-01
• Series: Nanomaterials
• Subjects: gold nanoparticles; methylated <i>RPRM</i> DNA; dynamic light scattering; gastric cancer; noninvasive detection
• Online Access: https://www.mdpi.com/2079-4991/9/9/1333

Reprimo (<i>RPRM</i>) is a tumor suppressor gene involved in the development of gastric cancer. Hypermethylation of the <i>RPRM</i> promoter region has been found in tumor tissue and plasma samples from patients with gastric cancer. These findings suggest that circulating methylated DNA of <i>RPRM</i> could be a candidate for a noninvasive detection of gastric cancer. We designed a nanosystem based on the functionalization of silica coated gold nanoparticles with oligonucleotides that recognize a specific DNA fragment of the <i>RPRM</i> promoter region. The functionality of the oligonucleotide on the surface of the nanoparticle was confirmed by polymerase chain reaction (PCR). The nanoparticles were incubated with a synthetic DNA fragment of methylated DNA of <i>RPRM</i> and changes in the size distribution after hybridization were evaluated by dynamic light scattering (DLS). A difference in the size distribution of nanoparticles hybridized with genomic DNA from the KATO III gastric cancer cell line was observed when was compared with DNA from the GES-1 normal cell line. These results showed that this nanosystem may be a useful tool for the specific and sensitive detection of methylated DNA of <i>RPRM</i> in patients at risk of developing gastric cancer.