Identification of osteosarcoma by microRNA-coupled nuclease digestion on interdigitated electrode sensor.

Osteosarcoma is a type of tumor originating from the bone cells, most often from long bones. Children and adolescents are mainly affected by osteosarcoma. Identifying the condition with osteosarcoma is mandatory to provide proper treatment to the affected patients. This research work has introduced an identification of an osteosarcoma biomarker "miRNA-21" on the interdigitated electrochemical sensor by nuclease digestion. The target RNA sequence of miRNA-21 was hybridized to the capture DNA and placed on the sensing electrode surface with the aid of the biotin-streptavidin interaction. The unhybridized immobilized single-standard capture DNA was digested by S1-nuclease. The current response of the digestion level was considered as the duplex formation between the target and capture DNA. Using this technique, the detection limit of the target was reached to 1 fM and a similar response of current was noted with the target RNA-spiked human serum, indicating the selective identification of target RNA. Further, single mismatched, triple mismatched, and random miRNA sequences (miRNA-195) failed to interact with the immobilized capture DNA, representing the specific identification of target RNA. This nuclease digestion technique with miRNA-21 identification helps in detecting osteosarcoma and related issues.

Nanomaterial-assisted determination of osteosarcoma by antibody-osteopontin-aptamer sandwich ELISA.

Immobilization and detection of small molecules is one of the challenging tasks in any given sensing system as the dissociation equilibrium constant is higher. Generating a right immobilization system with small molecules is mandatory for developing the drug-discovery process and disease identification. Immobilizing smaller probes on the ELISA plate is challenging because of its less adsorption on the polystyrene (PS) substrate. This research work developed an iron nanomaterial-based linker to attach osteopontin-specific aptamer on PS substrate. Iron oxide nanoparticle was attached on PS plate through amine modification and then antibody was attached by COOH reaction. On the osteopontin-modified plate, osteosarcoma biomarker of osteopontin was identified by its specific antibody and aptamer sandwich with the detection limit of 1 nM. Further, biofouling experiments with other molecules, such as lysozyme, and complementary aptamer failed to show the ELISA adsorption signal, indicating the iron oxide nanoparticle-modified PS plate specifically recognizes osteopontin. This research work effectively identifies the lesser abundance of osteopontin and helps to diagnose the osteosarcoma-related problems.

Silica nanoparticle-modified microcomb electrode for voltammetry detection of osteopontin with high sensitivity.

Osteosarcoma is a commonly occurring bone malignancy, and it is the second most common cause of cancer deaths in adolescents and children. A sensitive silica nanoparticle (Si-NP) modified current-volt sensor was introduced to identify the osteopontin antigen, a well-known biomarker for osteosarcoma. Si-NP was extracted from the rice husk ash and utilized for the surface functionalization on the interdigitated microelectrode sensing surface. Extracted Si-NP has a spherical shape with uniform distribution, and it is confirmed by field emission scanning electron microscopy and field-emission transmission electron microscopy. Si-NP was layered on the electrode surface through a (3-aminopropyl)triethoxysilane amine linker, and the antibody was immobilized on Si-NP through a glutaraldehyde linker. Osteopontin was effectively detected on the antibody-attached surface, and the determination limit was 0.6 ng/mL. The regression was determined as y = 0.9366x - 1.1113 and the R2 value was 0.9331 and the detection limit of osteopontin was 0.6 ng/mL in the range between 0.3 and 5 ng/mL. In addition, control performance with nonimmune antibodies and albumin did not change the current volt, showing the specific osteopontin identification. This research work brings out the easy and cost-effective method to diagnose osteosarcoma and its etiology.

Indirubin-3'-Oxime (IDR3O) Inhibits Proliferation of Osteosarcoma Cells in vitro and Tumor Growth in vivo Through AMPK-Activation and PGC-1α/TFAM Up-Regulation.

Osteosarcoma, a malignant tumor of bones, has very high incidence in adolescents and young people. The present study investigated the effect of indirubin-3'-oxime (IDR3O) derivative on proliferation of osteosarcoma cells in vitro and tumor growth in vivo. Changes in growth and induction of apoptosis in osteosarcoma cells were assessed using WST-8 and TUNEL staining assays. Treatment of MG63 and Saos­2 cells with IDR3O inhibited proliferation, activated apoptosis and promoted AMPK-activation. In IDR3O treated MG63 and Saos­2 cells PGC-1α (Peroxisome proliferator-activated receptor-γ coactivator-1α) levels were markedly promoted compared to control (untreated) cells. In the mice model osteosarcoma was induced by implantation of 2 × 106 MG63 cells on dorsal side subcutaneously. Then the experimental group of mice received IDR3O intra-peritoneally during 45 days. IDR3O-treatment suppressed tumor development significantly compared to control (untreated) group but didn't changed body weight. IDR3O inhibits osteosarcoma cell growth and activates apoptosis through AMPK dependent pathway. Therefore, IDR3O may be considered for treatment of osteosarcoma as it effectively arrests tumor growth in mice.