Sirna Synthesis

In making PNA a prospect for drugs, researchers have demonstrated proof of concept for using PNA oligomers to activated or suppress the transcription, replication, or repair of specific genes by binding DNA is various ways. PNA oligomers and conventional nucleic acids have the same problem of poor bioavailability because they are large water loving molecules making it difficult for them to enter cells. The productions of PNA based drugs awaits the development of suitable chemical modifications or pharmaceutical formulations to improve PNA bioavailability. Researchers believe this is the only thing holding back this medical breakthrough.

RNAi is defined as a mechanism of gene-silencing produced by small RNA fragments (siRNA/miRNA/shRNA) and it also can be described as posttranscriptional gene silencing3. These small RNAs have the ability to selectively bind and cleave cellular mRNAs and prevent their further expression3. This function holds great significance in cancer treatment and cell self-repairing1,3. The mechanism of RNAi therapy consists of multiple steps. Briefly, a double-strand small RNA fragment (~20bp) firstly incorporates into a multiprotein complex, RNA-Induced Silencing Complex (RISC), and their double strands starts unwinding after being activated. The single-stranded small RNAs product then guided activated RISC to identify mRNAs that are complementary to this single-stranded small RNA3,4. Once identified, this mRNA is cleaved by endoribonucleases and then degraded by exoribonucleases in

Gene silencing, the ability to selectively suppress the expression of a single gene, is something that was once thought of as a “holy grail” in medical technology. The potential treatments for this technology include, but are not limited to, inhibiting viral infections, cancer replication, and certain genetic disorders. Considering the potency of each of these problems within the modern medical field, the potential economic and physiological impact of gene silencing is massive (amounting to billions of dollars in investment). With the recent discovery of RNA interference (RNAi) (Fire and Mello) and the field’s development within the last 20 years, the impossible is starting to become possible.

As far as the structure guided chemical modification process the researchers began with HEK293 cells that were engineered to constitutively express GFP and spCAS-9. The reason they did this is the GFP protein was the target gene the researchers wanted to turn off since it is a simple way to observe editing effects and quantify levels of potency simply. After modifying various aspects of the sgRNA and exposing the HEK293 cells to each treatment they could simply take fluorescence readings and quantify how many cells were still expressing the GFP gene, and how many had been successfully edited. The modifications explored in this paper are modifications that had previously shown to decrease RNA’s susceptibility to nucleases in the blood,

The purpose of the study was to determine if tumor-directed gene therapy would be possible in a larger host. Positive results have been found in previous studies; however, these studies used rodents as the animal models. The goal was to see if these results could work on a different, larger animal model.

El-Aneed, A. (2004). An overview of current delivery systems in cancer gene therapy. Journal of Controlled Release, 94(1), 1-14.

So, the combination of ultrasound and transfection agents and Gene encapsulated in the agents could be a promising way to enhance gene delivery and transfection efficient significantly.

Herein, we report the PEG-LHRH peptide conjugated mTS-mPAE NPs for the targeted delivery of mTOR siRNA to the lung tumor cells, utilizing bioreducible cationic polymer mPAE based NPs as the delivery carrier. Towards this aim, mTS-mPAE NPs was synthesized using the nanoprecipitation method to encapsulate the mTOR siRNA and form mTS-mPAE NPS. The mTS-mPAE NPs was then conjugated with PEG and PEG-LHRH to form non-targeted(NT-NPs) and targeted (T-NPs) gene delivery system for the treatment of lung cancer. The NT-NPs and the T-NPs of uniform size, zeta potential were produced. The PEG and PEG-LHRH was conjugated on the NP surface by covalent conjugated.

Did you know that about 1,688,780 new types of cancer have been found in the United States, killing more than 600,920 people? Cancer has been known as the second leading cause of death in the United States just after Chronic Heart Disease. Fortunately, researchers have found a way to prevent and cure cancer and that is by using Nanotechnology. Nanotechnology is a branch in the science field that deals with dimensions less than 100 nanometers which is about a billionth of a meter. Not only that, but scientists predict that nanotechnology can lead to a major breakthrough in the medical field of Oncology. Researchers have now found a way to “tune” the nanoparticles so that the

It is possible to attach to these gold nanoparticles antibodies that specifically bind to proteins of interest and then tag these particles with identifiable DNA strands. The proteins of interest then bind to these antibodies which are attached to the gold nanoparticle, then then add another seeking antibody attached to a magnetic bead. Then magnets are used to separate the sample from everything around it and sequence the DNA strands.[3] If this same technique is used to hunt cancer proteins, it could be very easily used for early detection of cancer. This same principle can be used to image cancer cells. Just by switching the gold nanoparticle for a quantum dot(QD), this can then use the same seeking method as the gold nanoparticle and be used in imaging the tumor cells.[4] Another use for these gold nanoparticles is in gold nanoshells. These nanoshells can be injected into the area which the tumor is, and combined with the original seeking system mentioned earlier attach to the tumorous cells. These nanoshells can then be irradiated with a 820-nm, 4 W/cm² light pulses. The result found was that the area underwent a temperature change which caused the destruction of tumor cells. [1] This can be seen to be a very good way of treating the cancer cells as it leaves the surrounding cells untouched, and only ‘cooks’ the

In addition to peptides, protein-based ligands such as Affibody proteins have been utilized for tumor targeting. Anti-epidermal growth factor receptor (EGFR) Affibody protein (e.g., Ac-Cys-ZEGFR:1907, amino acid sequence: Ac-CVDNKFNKEMWAAWEEIRNLPNLNGWQMTAFIASLVDDPSQSANLLAEAKKLNDAQAPK-NH2) is used to target EGFR that is overexpressed in a wide variety of human tumors. Cheng and co-workers used anti-EGFR Affibody protein as tumor-targeting ligand on 64Cu–Au-IO nanoparticles (PET component: 64Cu, MRI component: iron oxide, specific for EGFR) surface.[63] In their work, A431 tumor cells were subcutaneously implanted in the right shoulders of nude mice; and 64Cu-NOTA-Au-IONP-Affibody nanoparticles were administered via tail vain injection. Rather low resolution PET image showed that these nanoparticles were taken by EGFR positive A431 (human epithelial carcinoma cell line) cells reaching 4.6% ID/g at 24 h after injection, significantly higher than that obtained from the blocking experiment (1.9% ID/g) indicating the specificity of the probe. This difference in % ID/g values corroborated with 44% drop in MRI signal intensity that was observed for the tumor. In this study, the use of an Affibody protein as ligand for EGFR-expressing tumor in small animals was demonstrated to be successful; however, the benefit of multimodality was not demonstrated. The unique chemistry of this dumbbell-shaped Au–IO nanoprobe could pave the way for targeted drug delivery into EGFR-expressing tumors

All statistical analysis in this proposal will be done in collaboration with the Ohio State University Comprehensive Cancer Center Biostatistics Shared Resource. All cell based studies in Aim 1 will be performed in triplicate. All results will be summarized using mean ± SEM, range and median for each continuous measurement and as proportions with confidence intervals for each dichotomous measurement. For in vivo studies proposed in Aim 2, 5 animals per arm will be utilized to validate in vivo impact of nanoparticle delivered drugs. Immunofluorescence analysis of resulting tumors will be compared for differences between the groups using ANOVA generating two-sided p-values, adjusting for the molecular subtype and accounting for repeated measures over time. For the 4 group comparison,

Since positively charged nanoparticles could easily uptake nucleic acids, we examined the possibility of using this new DDS to simultaneously deliver different chemotherapeutic drugs and siRNA targeting ABCG2. Our results demonstrated that both anti-tumor drugs and siRNA against ABCG2 were successfully delivered into CD133+ cancer cells of laryngeal carcinoma by loaded MSNs. Down regulation of ABCG2 significantly enhanced the efficacy of apoptosis induction by chemotherapeutic drugs in laryngeal carcinoma cells. Furthermore, the chemotherapeutic drug and siRNA loaded nanoparticles also inhibited tumor growth in vivo in a laryngeal cancer mouse model.

Advantages in nanoparticle drug delivery include improved pharmacokinetics, reduced side effects and longer circulation half-lives.1 In addition, nanoparticles may be able to achieve improved delivery of sparingly water soluble compounds by delivering a small particle size to increase the total surface area of the drugs allowing faster dissolution in the blood stream. These benefits have made therapeutic nanoparticles a promising candidate to replace conventional chemotherapeutic protocol, eliminating toxic agents and dose-limiting side effects which pose a threat to healthy tissues. The purpose of this review article on nanoparticles is to show the promise of delivering a range of molecules to desired sites in the body to treat cancer. In addition, it highlights numerous areas of opportunity where nanotechnology could enable innovative classes of therapeutics.

A study has been made which is (Therapeutic targeting of chitosan–PEG–folate-complexed oncolytic adenovirus for active and systemic cancer gene therapy) to overcome the issues of systemic delivery of Ad to increase its effectiveness; surface of Ad has been coated with cationic polymer chitosan by ionic crosslinking (Ad/chitosan). Then, folic acid (FA) or polyethylene glycol (PEG) was used to conjugate with the surface of Ad/chitosan, resulting in Ad/chitosan–FA, Ad/chitosan–PEG, and Ad/chitosan–PEG–FA nanocomplex. These nanocomplexes have good eliciting folate receptor (FR)-selective cancer cell killing efficacy. To evaluate cancer cell